Fix: stop misattributing undated usage to 'Today'

[darthrevanyunka]

What this fixes

Codeburn was misreporting Cursor usage by assigning undated records to the current day. This made Today appear artificially high, and the "most active day" could shift depending on when reports or menubar refreshes were run.

Root cause

Two parser paths generated synthetic "now" timestamps when source records were undated:

• Cursor bubble rows with missing createdAt
• Cursor agentKv sessions with no timestamp metadata

That rebucketed historical/undated usage into the runtime date.

Why this is important

• Daily usage charts become unreliable
• Menubar Today values can be misleadingly large
• Teams tracking token spend by day get incorrect trend signals

Changes

• Require real createdAt for bubble day bucketing (skip undated bubble rows)
• Stop defaulting agentKv timestamps to current time
• Parse timestamp candidates from agentKv content (timestamp, createdAt, and time* variants)
• Skip agentKv sessions when no reliable timestamp exists
• Add regression tests for all of the above

Verification

• npm test -- tests/providers/cursor.test.ts
• npm run build

Made with Cursor

[darthrevanyunka]

This PR is intended as a follow-up/complement to the recent Cursor provider fixes (including #257 and related work), focusing on one remaining day-bucketing edge case: undated records can still be assigned synthetic timestamps and drift into Today buckets.

What this PR tightens:

bubble rows: do not bucket rows without real createdAt into the current day
agentKv: avoid synthetic now bucketing; use embedded timestamp metadata when present, otherwise skip undated sessions
Why this matters:

prevents moving most-active-day behavior
keeps menubar and daily trend data consistent with actual event timing
Happy to split or trim scope if maintainers prefer this as a narrower patch.

[iamtoruk]

Nice catch on the undated bucketing - tested locally and the fix is solid. Two small things before we merge:

1. takeUserMessage() (line 197) is now unused since you inlined the shift. Can you remove it?
2. Line 528 still passes source.path as a third arg to parseAgentKv but the signature only takes two params now. Harmless but should match.

Happy to merge once those are cleaned up.

[darthrevanyunka]

All done and tested