Fix #5298: Update apply_diff tool description to mark :start_line: as optional

[roomote]

Fixes #5298 by updating apply_diff tool descriptions in Human Relay Mode to correctly mark :start_line: as optional instead of required. Updated both MultiSearchReplaceDiffStrategy and MultiFileSearchReplaceDiffStrategy getToolDescription() methods to align with official documentation.

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Important

Update apply_diff tool description in getToolDescription() methods to mark :start_line: as optional in multi-file-search-replace.ts and multi-search-replace.ts.

• Tool Description Update:
  • In multi-file-search-replace.ts and multi-search-replace.ts, update getToolDescription() to mark :start_line: as optional in the apply_diff tool description.
  • Aligns description with official documentation.
• Behavior:
  • No functional changes, only documentation update within code comments.

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[delve-auditor]

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• 🔎 Scanned files: 2 changed file(s)

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