Add current-tab context extraction

[zhongnansu]

Summary

• Adds default current-tab context extraction for selected-text chat without sending raw full-page text
• Scores and formats page headings, nearby selected-text context, and important page excerpts while excluding forms/editable fields and common page chrome
• Wires extracted context through toolbar, bubble preset/custom, and context-menu chat paths
• Raises prompt/proxy text budget to 64k chars and bumps extension/package version to v1.4.0
• Updates README and privacy docs for the new default context behavior

Closes #206
Closes #207
Closes #208

Validation

• npm run typecheck
• npm test
• npm run build
• npm run test:e2e

Release

• Intended minor release: v1.4.0
• manifest.json, package.json, and package-lock.json are aligned at 1.4.0

[github-actions]

📦 PR Preview — Ask AI Extension

Version: 1.4.0
Zip size: 1169.7 KB

⬇️ Download artifact

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Permissions

No permission changes detected. ✅

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Preview Checklist

Before merging, manually test with the artifact above:

• Load unpacked extension in chrome://extensions (developer mode)
• Select text on any webpage and verify the trigger button appears
• Click the trigger button and confirm the popup renders correctly
• Right-click selected text and verify context menu items are present
• Open a CSP-restricted page (e.g. chrome://extensions) and verify fallback works
• Check the DevTools console for errors

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Updated by PR Preview Bot — workflow run

[github-actions]

📊 Code Coverage Report

File	Coverage	Status
proxy/src/index.ts	98.0%	🟢
proxy/src/openai.ts	100.0%	🟢
proxy/src/rate-limit.ts	100.0%	🟢
proxy/src/validate.ts	95.4%	🟢
src/options.tsx	91.5%	🟢
src/popup.tsx	100.0%	🟢
src/background/index.ts	83.3%	🟢
src/content/api.ts	87.5%	🟢
src/content/detection.ts	100.0%	🟢
src/content/history.ts	82.5%	🟢
src/content/image-capture.ts	89.0%	🟢
src/content/page-context.ts	92.2%	🟢
src/content/presets.ts	100.0%	🟢
src/content/prompt.ts	88.5%	🟢
src/content/autosuggest/context.ts	98.5%	🟢
src/content/autosuggest/debounce.ts	100.0%	🟢
src/content/autosuggest/editor.ts	87.6%	🟢
src/content/autosuggest/ghost-text.ts	97.4%	🟢
src/content/autosuggest/index.ts	82.9%	🟢
src/content/autosuggest/styles.ts	100.0%	🟢
src/content/bubble/core.tsx	95.3%	🟢
src/content/bubble/history.ts	80.0%	🟢
src/content/bubble/legacy-copy-button.ts	100.0%	🟢
src/content/bubble/markdown.ts	95.3%	🟢
src/content/bubble/shell.tsx	94.8%	🟢
src/content/bubble/stream.ts	94.3%	🟢
src/content/bubble/styles.ts	100.0%	🟢
src/content/bubble/view-model.ts	100.0%	🟢
src/content/shared/constants.ts	100.0%	🟢
src/content/shared/dom-utils.ts	100.0%	🟢
src/content/shared/preset-usage.ts	90.6%	🟢
src/content/shared/state.ts	100.0%	🟢
src/content/trigger/button.tsx	89.8%	🟢
src/content/trigger/progress-ring.ts	100.0%	🟢
src/content/trigger/screenshot.ts	98.5%	🟢
src/content/trigger/selection.ts	71.2%	🔴
src/content/trigger/styles.ts	100.0%	🟢
src/content/trigger/toolbar-shell.tsx	100.0%	🟢
src/shared/autosuggest-limits.ts	100.0%	🟢
src/shared/brand.ts	100.0%	🟢
src/shared/color-palette.ts	100.0%	🟢
src/shared/model-config.ts	100.0%	🟢
src/shared/react-root.tsx	100.0%	🟢
src/shared/runtime-messages.ts	100.0%	🟢
src/shared/storage.ts	93.3%	🟢
src/shared/theme.ts	73.6%	🔴
Overall	93.6%	🟢 PASS

Threshold: 80%

✅ Coverage meets the minimum threshold.

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Updated by Code Coverage workflow