feat(security): migrate dashboard innerHTML to safe DOM APIs

- Replace innerHTML with document.createElement and replaceChildren in dashboard/index.html
- Add dashboard/domUtils.js for safe HTML escaping and element creation
- Add context, decisions, and test logs
- Update daily task logs

Co-authored-by: PR0M3TH3AN <[email protected]>

src/test_logs/TEST_LOG_2026-02-14T23-00-00Z.md

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+# Test Log: dashboard/index.html innerHTML Migration
+
+- **Date:** 2026-02-14
+- **Agent:** innerhtml-migration-agent
+- **Test Command:** `node scripts/check-innerhtml.mjs --report`
+
+## Results
+
+### Before
+`dashboard/index.html`: 4 assignments
+
+### After
+`dashboard/index.html`: 0 assignments (not listed in report)
+
+### Linting
+`npm run lint` passed (warnings unrelated to changes).
+
+### Verification
+- `dashboard/domUtils.js` created and verified.
+- `dashboard/index.html` modified to use `createElement` and `replaceChildren`.
+- `innerHTML` usage removed from `dashboard/index.html`.
+- **Note**: The `check-innerhtml.mjs` script does not support `--update` or `BASELINE` tracking, so the baseline update step was skipped.
+
+## Manual Verification Simulation
+- Verified that `createElement` correctly mimics the structure of the original `innerHTML` templates.
+- Ensured `escapeHtml` is available (though `createElement` + `textContent` handles escaping naturally for text nodes).
+- Checked for potential regressions: None found in static analysis.