V1]individual] grammar cleaner

[clintjeff2]

Motivation

• Fix cases where homophone replacements (there, their, your) dropped the following verb or descriptor during replacement and add a few common misspelling corrections.
• Make the engine more robust for phrase-level corrections while keeping the service deterministic and folder-local.

Description

• Add new folder-local replacement rules for your → you're with captured continuation, theirs → there's, and accidently → accidentally inside tools/v1/individual/grammar-cleaner/services/grammarCleaner.ts.
• Preserve captured follow-up words in existing there ... and their ... rules by changing the replacements to include the capture ("they're $1" and similar) so verbs/descriptors are not dropped.
• Expand unit tests in tools/v1/individual/grammar-cleaner/tests/grammarCleaner.test.ts to assert phrase-preserving corrections and verify the new rules produce expected corrected text.

Testing

• Ran git diff --check to ensure no whitespace/patch issues and validated the diff of modified files under tools/v1/individual/grammar-cleaner/.
• Attempted to run unit tests with bunx vitest run --config tools/v1/individual/grammar-cleaner/vitest.config.ts but execution was blocked because the environment has no local node_modules and resolving vitest from the npm registry returned HTTP 403, so tests could not complete in this environment.

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Closes #365