Support sorting in the list command and add an 'ls' alias

[dmccoystephenson]

Summary

• A --sort / -s option has been added to the list command. Supported values are name, impact, confidence, ease, reach, effort, ice and rice; matching is case-insensitive.
• Sorting is delegated to a new ProjectSorter.sortBy(List<Project>, String) method, so the existing sorting component is reused rather than duplicated. name is ordered alphabetically (case-insensitive, A to Z); every other key is ordered highest to lowest, matching the existing score-sorting behavior used by the export command.
• Existing behavior has been preserved: when --sort is omitted, projects are still listed in creation order and the header remains Projects:. When a sort is applied, the header reports it as Projects (sorted by <key>):.
• An unsupported sort value is rejected with a message naming every supported value, following the error style already used by ExportProjectsCommand.
• ls has been registered as an alias for list via the @ShellMethod key array.
• README.md has been updated with the alias, a List Examples block, and the supported sort values. A hardcoded test count in CONTRIBUTING.md was found to be stale and has been replaced with a non-brittle statement, since this PR changes that count again.

Test plan

• ./gradlew test passes locally (78 tests).
• ProjectSorterTest covers the new sortBy method: null list, unsupported key, name ordering, integer-field ordering (impact, effort), RICE ordering, mixed-case keys, original-list immutability, and the isSupportedSortKey / getSupportedSortKeys helpers.
• ListProjectsCommandTest covers creation-order preservation, name sorting, ice sorting, case-insensitive keys, rejection of an unsupported key, and registration of the ls alias.
• Existing ProjectSorter and export behavior is untouched; the pre-existing sortByScore / sortByIce / sortByRice tests still pass unchanged.

Deferred issues

The remaining open backlog was not selected for this cycle, for the reasons below:

• Allow user to quit early during project creation #37 (quit early during project creation) — the interactive creation input flow is a separate subsystem from listing.
• Add installation script for Linux #36 (Linux installation script) — packaging work, unrelated to this batch.
• Save data to user's home directory by default #33 (save data to the user's home directory) — modifies src/main/resources/application.yaml, a path that is gated for human review.
• Create directory for JSON storage if it doesn't already exist #32 (create the JSON storage directory if missing) — storage-layer work that pairs naturally with Save data to user's home directory by default #33 and is better done alongside it.
• Add controller endpoints to create, retrieve, update and delete projects #27 (controller endpoints) — introduces a web layer; too large for a polish-sized PR.
• Update command #21 (update command) and Delete command #20 (delete command) — each is its own command-plus-persistence change.
• Input validation w/ Jakarta #8 (input validation with Jakarta) — requires a new dependency in build.gradle, a path that is gated for human review.

Closes #29
Closes #34

This PR description was drafted during a Gardener session (https://github.com/Stephenson-Software/gardener).

[github-actions]

Test Results

78 tests  +17   78 ✅ +17   1s ⏱️ ±0s
14 suites ± 0    0 💤 ± 0 
14 files   ± 0    0 ❌ ± 0 

Results for commit 5eb8d67. ± Comparison against base commit b4ef20c.

[dmccoystephenson]

Self-review rubric

Scored adversarially against the diff and command output, not from judgment alone.

• Manual validation / CI (external anchor): PASS — ./gradlew test passes locally (78 tests, 0 failures) and both GitHub Actions workflows are green on the PR head (build (21) pass, test pass, Test Results pass).
• Scope: PASS — six files are touched and each is required by Support sorting in list command #29 or Add 'ls' alias for list command #34: ListProjectsCommand and ProjectSorter (implementation), their two test classes, and README.md. One caveat is disclosed below regarding CONTRIBUTING.md.
• Tests-new: PASS — every new public method is exercised. ProjectSorter.sortBy is covered by seven new tests, isSupportedSortKey by two, and getSupportedSortKeys by one; the new execute(String) signature is covered by six new ListProjectsCommandTest cases.
• Tests-fix (empirical mutation, not reasoning): PASS — although this is a feature rather than a bug fix, the regression value of the new tests was confirmed by mutation rather than by argument. With key = {"list", "ls"} reverted to key = {"list"} and boolean sorted forced to false, ./gradlew test --tests ListProjectsCommandTest reported 8 tests completed, 5 failed (shouldExposeLsAsAnAliasForTheListCommand, shouldSortByNameWhenNameSortIsRequested, shouldSortByIceWhenIceSortIsRequested, shouldAcceptSortKeyRegardlessOfCase, shouldRejectUnsupportedSortKey). Both mutations were reverted and the full suite re-run green; git diff --stat confirmed an empty working tree afterwards.
• Sibling structure: PASS with a caveat — the --sort option, its @ShellOption(value = {"-s", "--sort"}) declaration, and the Invalid sort option. error style all mirror ExportProjectsCommand. The caveat is recorded under Findings below.
• Sibling renames: PASS — no identifier in a parallel pair or series was renamed; sortByScore / sortByIce / sortByRice are untouched and their existing tests still pass unchanged.
• Docs: PASS — README.md's command list now records the ls alias and the sort option, and a List Examples block documents every supported value. CONTRIBUTING.md's ./gradlew test instruction remains accurate.
• Issue resolution: PASS — Support sorting in list command #29's named surface area (list command sorting, including by name and by score) is implemented with eight sort keys; Add 'ls' alias for list command #34's (ls alias) is implemented via the @ShellMethod key array and asserted by test.
• Shell command tests: PASS — the changed @ShellComponent has a corresponding ListProjectsCommandTest exercising its @ShellMethod.
• Round-trip coverage: not applicable — no field was added to Project or any other Lombok domain class, so ProjectJsonReaderWriterImplTest needs no change.
• I/O behind an interface: not applicable — no new code touches the filesystem or console input.

Findings

Three observations are recorded rather than fixed, since each is a judgment call or would widen scope:

1. src/main/java/com/preponderous/parpt/export/ProjectSorter.java — a general-purpose sortBy method has been added to a class living in the export/ package, yet its first caller is now the list command rather than an export path. Duplicating the comparator logic into a second class was judged worse than the package mismatch, so reuse was chosen. Relocating the class to a neutral package would touch ProjectMarkdownWriterImpl and the export tests, which is out of scope here.
2. src/main/java/com/preponderous/parpt/export/ProjectSorter.java — two sorting entry points now coexist: the older boolean-flag sortByScore(List, boolean) used by markdown export, and the new key-based sortBy(List, String). Converging ProjectMarkdownWriterImpl and ExportProjectsCommand onto the key-based API would remove the duplication, but it changes export behavior and belongs in its own PR. A follow-up issue has been filed.
3. README.md:69 — the short form list -s impact is documented on the strength of the explicit @ShellOption(value = {"-s", "--sort"}) declaration, matching what ExportProjectsCommand already declares. The new tests invoke execute(String) directly, so Spring Shell's option-parsing layer itself is not covered by any test in this repo; the short form is declared but not exercised end to end.

Scope disclosure

CONTRIBUTING.md was edited by one line beyond the two issues. Its Continuous Integration section claimed "currently 58 tests", a figure this PR invalidates (the suite now stands at 78). The hardcoded count was replaced with a non-brittle statement rather than being updated to a number that would drift again on the next PR.

This comment was drafted during a Gardener session (https://github.com/Stephenson-Software/gardener).