feat: fingerprint-healed replay with checkpoints, offline HAR, and replay export via codegen

[cdg-me]

• store each recorded element interaction with its fingerprint and position among identical siblings, enabling identity-based relocation on replay
• record expect calls as checkpoint events that replay enforces through the same wait loop as /expect
• add record start --capture-har: network capture with bodies written as HAR alongside the recording
• replay offline by default: recorded responses served via snapshot router; --live clears it and hits the network
• replay with --session : restore a saved session (cookies restored) before running
• report replay outcome as JSON: steps, checkpoints total/passed, healed substitutions (from → to selectors), failed step, duration; failures exit 1 at the CLI with the report rendered
• heal through UI drift: selector no longer matching its fingerprint triggers relocation by fingerprint plus occurrence index, reported as healed
• fail loudly on semantic change: replaced or relabelled elements stop replay at that step naming the original identity and prior checkpoint results
• convert per-step panics into report errors (a failed navigation previously reported success)
• fix replayed js events skipping bare-expression wrapping and type interpolating selectors into single-quoted JS
• keep capture control commands out of recordings so replayed HAR flows don't replay capture itself
• default replay speed to instant; recorded timing available via --speed 1
• add record export: pure codegen to a Playwright spec with role-based locators, .nth() disambiguation for repeated elements, assertions with timeouts, routeFromHAR, and selector-provenance comments; verified passing under npx playwright test on both canonical and drifted UI
• persist cookies in session save/resume
• add shop fixture with canonical/drifted/broken variants; 10 replay e2e tests and 4 export unit goldens
• document replay semantics in QUICKSTART and add a fingerprint-bearing recording preset