ci(playwright): detect hogql-parser changes with the paths filter - #125835

Problem

• Every Playwright run fetches master to detect parser changes before tests start.
• On 98 queue runs (2026-10-29) this took 39 s median, 373 s max (slowest).

Changes

The changes job now decides whether to build the parser.

flowchart LR
    A[changes<br/>paths filter] --> B[playwright<br/>fetch master, git diff] --> C[build parser<br/>if changed]
    class A,C phBlue;
    class B phRed;
    classDef phBlue fill:#1d4aff,stroke:#1d4aff,color:#fff;
    classDef phRed fill:#f54e00,stroke:#f54e00,color:#fff;

flowchart LR
    A[changes<br/>paths filter + hogqlParser] --> C[playwright<br/>build parser if changed]
    class A,C phBlue;
    classDef phBlue fill:#1d4aff,stroke:#1d4aff,color:#fff;

• The existing pulls.listFiles call answers a new hogqlParser filter. No new token.
• It diffs against the merge base, so an unrebased branch stops rebuilding a parser only master changed.
• Master runs still skip the build.
• Dispatched branches always build, so a forced draft run tests its own parser.

How did you test this code?

• PR run: hogqlParser = false, build skipped.
• Dispatch run: the fallback built the parser in 136 s.
• Not run: a PR that changes the parser.

Test rationale: Not needed. The stubbed plan covers the changed condition.

Release status

• None.

Docs update

• None.

🤖 Agent context

Autonomy: Human-driven (agent-assisted)

Agent: Claude Code, claude-opus-5-5

Skills: /authoring-ci-workflows, /writing-pr-descriptions, /writing-code-comments