fix: Properly handle keys with whitespace around dot-separated parts

[DecimalTurn]

I disapprove of how you format your TOML files, but I will defend to the death your right format it in that way.
- Anonymous

Whitespace around dot-separated parts is ignored. However, best practice is to not use any extraneous whitespace.
- TOML Spec

Example:

fruit.name = "banana"       # this is best practice
fruit. color = "yellow"     # same as fruit.color
fruit . flavor = "banana"   # same as fruit.flavor

This PR fixes patching issues caused by the use of extranous whitespace in dotted-keys.
Also, since the original fuzzer didn't emit TOML data with this feature, a seperate fuzzer (wrapper) was created to generate that type of TOML data.

[Copilot]

🟡 Changes recommended

The parser’s dotted-key raw reconstruction currently normalizes separator whitespace to spaces (losing tabs), and there’s a duplicated test block that should be removed.

Once you've addressed the issues Copilot identified, you can request another Copilot review.

Pull request overview

This PR improves toml-patch’s handling of TOML dotted keys that contain whitespace around dot separators, ensuring patch operations preserve the original key formatting (and adds a second fuzz harness to exercise this syntax).

Changes:

• Preserve whitespace around dotted-key separators when inserting/renaming keys (including table headers) during patching.
• Update parsing to retain spacing around dotted key separators in key.raw.
• Add targeted regression tests plus a new fuzz harness/runner (fuzz2) and a stability test locking the fuzz inputs.

File summaries

File	Description
src/patch.ts	Adds helpers to detect/reapply dotted-key separator spacing and uses them during inserts/renames.
src/parse-toml.ts	Adjusts dotted-key raw reconstruction to include spacing around . separators.
src/tests/patch.indentation.test.ts	Updates commentary around potential future multiline formatting options.
src/tests/patch.dotted-key-spacing.test.ts	Promotes previously failing dotted-key spacing tests to passing and adds broader coverage for spaced table titles and related ops.
src/tests/fuzz-stability.test.ts	Locks fuzz-generated TOML inputs via length + SHA-256 to make fuzz inputs stable over time.
src/tests/fuzz-patch2.ts	Introduces a fuzz harness variant that spaces dotted-key separators before patching.
src/tests/fuzz-patch.ts	Extends fuzz runner to support source transforms and optional indent-width randomization.
scripts/fuzz-run2.ts	Adds a CLI runner for the second fuzz harness.
package.json	Adds npm run fuzz2 script for the new fuzz runner.
docs/Formatting.md	Clarifies legacy anonymous formatting object usage vs recommended type-safe approach.

Review details

• Files reviewed: 11/11 changed files
• Comments generated: 3
• Review effort level: Lite

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