[T613] Expose directory evidence for existence checks

[ai21z]

Summary

• Add a read-only path-existence tool surface for filename existence questions
• Expose talos.list_dir plus talos.read_file for existence/path-status prompts while keeping mutation and command tools hidden
• Preserve targeted file-read narrowing for ordinary Read file prompts

Verification

• RED: ToolSurfacePlannerTest.fileExistenceQuestionsExposeDirectoryAndFileReadEvidenceTools failed before implementation
• ./gradlew.bat test --tests "dev.talos.runtime.toolcall.ToolSurfacePlannerTest" --no-daemon
• ./gradlew.bat test --tests "dev.talos.runtime.toolcall.*" --no-daemon
• git diff --check
• ./gradlew.bat validateArchitectureBoundaries --no-daemon
• ./gradlew.bat check --no-daemon

[chatgpt-codex-connector]

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[chatgpt-codex-connector]

Keep “present” from widening ordinary read prompts

For prompts like “Present README.md as bullet points,” TaskContractResolver extracts README.md as an expected target and this substring check treats the imperative verb “present” as an existence question. That changes the surface from the narrow expected target read path to talos.list_dir + talos.read_file, allowing directory enumeration even though the user only asked to format/read a named file. Please restrict this to status phrasing such as is/are present rather than any occurrence of present.

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