Init: preserve repository config in easy mode

CHANGELOG.md

@@ -12,6 +12,10 @@ later entries are regular releases.
   and Claude lanes in one run no longer make publication ambiguous, while a
   missing, duplicate, wrong-job, or wrong-attempt seal still fails closed
   (#1032).
+- `code-mower init --easy` now preserves an existing root `code-mower.yml` for
+  previews and staged applies. Applying packaged starter defaults beside an
+  existing config requires `--packaged-starter`, remediation prints exact
+  preview/apply commands, and generated lane-config paths are unique (#1054).
 - Hosted-agent installation guidance now includes a Python-based uv bootstrap
   that does not pipe a remote script into a shell. Remote-only orchestrators
   get an explicit packaged-starter doctor command, doctor JSON is identified as

docs/try-in-10-minutes.md

@@ -107,6 +107,19 @@ code-mower init --easy --apply --output-dir .code-mower.generated
 `init --easy` is non-mutating by default. `--apply` writes a generated tree for
 review in `.code-mower.generated`, creates the missing Code Mower labels when
 GitHub access allows it, and still does not trigger reviewers or upload data.
+When the checkout already has a root `code-mower.yml`, easy mode renders from
+that repository configuration so an upgrade keeps its selected lanes and
+policy. To deliberately stage starter defaults instead, name that choice:
+
+```bash
+code-mower init --easy --packaged-starter --apply \
+  --output-dir .code-mower.generated
+```
+
+An apply that would otherwise choose the packaged starter while a root config
+exists is refused with the exact repository-config and explicit-starter commands.
+Use `code-mower migration setup-drift --repo-path .` before copying generated
+upgrade files into the checkout.
 
 The generated tree includes local Codex and Claude audit lanes, the
 `code-mower/gate` workflow, stale-audit cleanup, owner escalation labels, and

docs/upgrade-existing-repo.md

@@ -63,16 +63,20 @@ repository setup upgrade follows below.
 From a clean repository checkout:
 
 ```bash
+code-mower init --easy
 code-mower init code-mower.yml --profile PROFILE --dry-run
 code-mower init code-mower.yml --profile PROFILE --apply \
   --output-dir .code-mower.generated
 ```
 
-Replace `PROFILE` with the profile the repository already uses. This explicit
-config path preserves its participant, lane, and policy choices while rendering
-the v1.5.0 support files. If the repository truly has no `code-mower.yml`, use
-`code-mower init --easy --apply --output-dir .code-mower.generated` and review
-the packaged starter as a new adoption.
+Easy mode now detects a root `code-mower.yml` and previews from it. Replace
+`PROFILE` with the profile the repository already uses when you run the explicit
+commands. Both forms preserve participant, lane, and policy choices while
+rendering the installed package's support files. If the repository truly has no
+`code-mower.yml`, use `code-mower init --easy --apply --output-dir
+.code-mower.generated` and review the packaged starter as a new adoption. If a
+root config exists and you intentionally want starter defaults, make that choice
+explicit with `--packaged-starter`.
 
 Treat `.code-mower.generated` as review input. Do not copy it wholesale until
 you have compared it with the existing repository files.

src/code_mower/init.py

@@ -193,8 +193,6 @@ def _audit_workflow_paths(lane):
     ("tools/audit_publication.py", "audit_publication.py", "product-support-helper", "0644"),
     ("tools/trailer_comment_labeler.py", "trailer_comment_labeler.py", "product-support-helper", "0644"),
     ("tools/lane_configs/__init__.py", "lane_configs/__init__.py", "product-support-helper", "0644"),
-    ("tools/lane_configs/claude.py", "lane_configs/claude.py", "product-support-helper", "0644"),
-    ("tools/lane_configs/codex.py", "lane_configs/codex.py", "product-support-helper", "0644"),
     (
         "tools/builder_lineage.py",
         "builder_lineage.py",
@@ -2531,12 +2529,35 @@ def setup_drift_next_step(*, profile_id: str) -> str:
     return (
         "root code-mower.yml exists but the packaged starter config was selected; "
         f"rerun with `code-mower init code-mower.yml --profile {quoted_profile} --dry-run` "
-        "to use the explicit repository config, or compare with "
+        "to preview the repository config, then stage the upgrade with "
+        f"`code-mower init code-mower.yml --profile {quoted_profile} --apply "
+        f"--output-dir {DEFAULT_APPLY_OUTPUT_DIR}`; compare with "
         "`code-mower migration setup-drift --repo-path .` "
         "(see docs/upgrade-existing-repo.md)"
     )
 
 
+def implicit_starter_apply_error(*, profile_id: str, output_dir: str) -> str:
+    """Explain how to stage either safe config source after refusing ambiguity."""
+
+    quoted_profile = shlex.quote(profile_id)
+    quoted_output_dir = shlex.quote(output_dir)
+    repository_command = (
+        f"code-mower init {ADOPTION_CONFIG_PATH} --profile {quoted_profile} --apply "
+        f"--output-dir {quoted_output_dir}"
+    )
+    starter_command = (
+        f"code-mower init --packaged-starter --profile {quoted_profile} --apply "
+        f"--output-dir {quoted_output_dir}"
+    )
+    return (
+        f"root {ADOPTION_CONFIG_PATH} exists; refusing to apply the packaged starter "
+        "without an explicit selection. Preserve the repository configuration with "
+        f"`{repository_command}`, or explicitly select the packaged starter with "
+        f"`{starter_command}`"
+    )
+
+
 def render_init_plan(
     config: Mapping[str, Any],
     profile_id: str = "recommended",
@@ -2769,12 +2790,21 @@ def render_init_plan(
                 warnings.append(f"{lane_id}: generated file {path} collides with another lane")
             else:
                 generated_paths.add(path)
-                generated_files.append(
-                    {
-                        "path": path,
-                        "source": "lane-config-template",
-                    }
-                )
+                entry = {"path": path, "source": "lane-config-template"}
+                # Claude and Codex used to be emitted twice: once here as a
+                # placeholder and once through PRODUCT_SUPPORT_FILES as the
+                # real package helper. Keep the fix deliberately scoped to
+                # those two duplicate entries; other lane templates retain
+                # their established placeholder behavior.
+                if trailer_module in {"claude", "codex"}:
+                    entry.update(
+                        {
+                            "copy_from": f"src/code_mower/lane_configs/{trailer_module}.py",
+                            "package_copy_from": f"lane_configs/{trailer_module}.py",
+                            "package_copy_first": True,
+                        }
+                    )
+                generated_files.append(entry)
         smoke_tests.extend(_lane_smoke_tests(lane_id, lane, package_mode=package_mode))
         warnings.extend(_lane_warnings(lane_id, lane, package_mode=package_mode))
 
@@ -3507,8 +3537,16 @@ def main(argv: list[str] | None = None) -> int:
     args = parser.parse_args(argv)
 
     explicit_config = args.config is not None
+    has_root_config = root_adoption_config_present()
     if args.config is None:
-        args.config = PACKAGED_STARTER_CONFIG_NAME
+        # Easy mode is also the upgrade entrypoint people remember. Preserve an
+        # existing repository's selected policy instead of silently switching
+        # the generated tree back to starter defaults.
+        args.config = (
+            ADOPTION_CONFIG_PATH
+            if args.easy and has_root_config and not args.packaged_starter
+            else PACKAGED_STARTER_CONFIG_NAME
+        )
 
     if args.easy:
         args.profile = "recommended"
@@ -3557,6 +3595,15 @@ def main(argv: list[str] | None = None) -> int:
             # basename matches the starter; only a resolved packaged fallback
             # counts as the packaged starter.
             packaged_fallback = config_source != Path(args.config)
+        if args.apply and packaged_fallback and has_root_config and not args.packaged_starter:
+            print(
+                "error: "
+                + implicit_starter_apply_error(
+                    profile_id=args.profile, output_dir=args.output_dir
+                ),
+                file=sys.stderr,
+            )
+            return 1
         rendered_config_path = (
             str(config_source) if packaged_fallback else args.config
         )