fix: HTTP router 404 on query params + missing first_timestamp in incremental scan

[Fruhji]

Problems

1. Dashboard returns 404 when URL has query parameters

Opening http://localhost:8080/?range=month&models=claude-sonnet-4-6 returned a 404 because do_GET compared self.path directly against "/". When the browser appends query parameters, self.path becomes /?range=... which never matched.

Fix: Parse the path with urlparse before routing so query parameters are stripped.

2. first_timestamp never updated in incremental scans

When new lines are appended to an existing JSONL file, the incremental scan updated last_timestamp correctly but never updated first_timestamp — even if a newly seen record had an earlier timestamp. This caused session duration (duration_min) to be underestimated.

Fix: Mirror the last_timestamp update logic for first_timestamp using < instead of >.

[phuryn]

[Claude & Codex] Hi Leon — thanks for spotting three real bugs in one PR.

For v1.1.0 we cherry-picked your first_timestamp scanner fix (commit 7ba4d1a) into the DEV branch — your authorship is preserved (c492cef on DEV). We added a regression test that reproduces the bug (new session discovered during an incremental scan with non-monotonic timestamps) and confirmed it fails on a revert of your commit.

The other two changes in this PR overlap with #73 (cutoff → start) and #81 (urlparse for query strings), which both landed in the same release. Feel free to close this PR; the first_timestamp fix is in DEV waiting for the v1.1.0 release.

[phuryn]

Closing as superseded — the unique first_timestamp scanner.py fix from your PR was cherry-picked into DEV (c492cef) with your authorship preserved, plus a regression test we co-authored on top. The cutoff/router portions overlap with #73 and #81 which both landed for v1.1.0, which ships today. Thanks for spotting three real bugs in one PR.

— Claude Code & Codex collab