chore(tools): ban as any via eslint and fix existing usages

[pavelfeldman]

Summary

• Add no-restricted-syntax ESLint rule targeting as any casts in tools code to prevent accidental casting to client interfaces
• Replace as any with precise types where possible (e.g. Parameters<playwright.Frame['getByRole']>[0], zod issue discriminated union)
• Add eslint-disable comments with justification for remaining unavoidable as any usages
• Minor cleanups: simplify sanitizeUnicode, tighten callTool signature, remove dead code in sessionLog

🤖 Generated with Claude Code

[github-actions]

Test results for "MCP"

5339 passed, 186 skipped

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Merge workflow run.

[github-actions]

Test results for "tests 1"

11 failed
❌ [default] › run-tests.spec.ts:226 › should show error message @vscode-extension
❌ [default] › run-tests.spec.ts:278 › should show soft error messages @vscode-extension
❌ [default] › run-tests.spec.ts:818 › should report project-specific failures @vscode-extension
❌ [default-reuse] › run-tests.spec.ts:226 › should show error message @vscode-extension
❌ [default-reuse] › run-tests.spec.ts:278 › should show soft error messages @vscode-extension
❌ [default-reuse] › run-tests.spec.ts:818 › should report project-specific failures @vscode-extension
❌ [default-trace] › run-tests.spec.ts:226 › should show error message @vscode-extension
❌ [default-trace] › run-tests.spec.ts:278 › should show soft error messages @vscode-extension
❌ [default-trace] › run-tests.spec.ts:383 › should only create test run if folder belongs to context @vscode-extension
❌ [default-trace] › run-tests.spec.ts:818 › should report project-specific failures @vscode-extension
❌ [playwright-test] › playwright.reuse.browser.spec.ts:102 › should produce correct test steps @ubuntu-latest-node20

6 flaky

⚠️ [chromium-library] › library/video.spec.ts:358 › screencast › should capture navigation `@chromium-ubuntu-22.04-arm-node20`
⚠️ [chromium-library] › library/trace-viewer.spec.ts:1223 › should display language-specific locators `@chromium-ubuntu-22.04-node24`
⚠️ [chromium-library] › library/trace-viewer.spec.ts:1223 › should display language-specific locators `@chromium-ubuntu-22.04-node22`
⚠️ [firefox-library] › library/inspector/cli-codegen-1.spec.ts:1080 › cli codegen › should not throw csp directive violation errors `@firefox-ubuntu-22.04-node20`
⚠️ [firefox-page] › page/page-wait-for-function.spec.ts:104 › should work with strict CSP policy `@firefox-ubuntu-22.04-node20`
⚠️ [webkit-library] › library/har.spec.ts:163 › should include form params `@webkit-ubuntu-22.04-node20`

38764 passed, 847 skipped

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Merge workflow run.