fix(web): clarify the interview invitation incentive copy

[Rinat S (rsolmano)]

Problem

The user-interview invitation (automatic prompt and Settings → Feedback) read "Join us for a user interview, tell us about your experience with ThinkRail, and receive 100 bonus credits…". It ran the ask and the reward together, so it could be read as promising credits for joining or booking, rather than for completing an interview.

Approach

Reword the shared INTERVIEW_INVITATION_COPY into two sentences: what we ask (tell us about your experience in a user interview), then when the reward applies (after you complete the interview). It stays strictly in credits with no currency amount, and it makes no new promises about duration or fulfillment, since attendance verification and crediting happen outside the app.

New copy:

Tell us about your experience with ThinkRail in a user interview. After you complete the interview, you will receive 100 bonus credits in Central (JetBrains AI).

Changes

• apps/web/src/panels/interview.ts: new invitation copy, shared by InterviewPromptDialog and FeedbackSettings.
• apps/web/src/panels/SPEC.md: the Feedback section now says completing an interview earns the credits, which are never a currency amount.
• e2e/feedback.spec.ts: expected copy updated.

Screenshots

	Before	After
Interview prompt
Settings → Feedback

Related issues

None.

Checklist

• Fast gates pass: bun run lint, bun run typecheck, bun run test
• E2E suite passes for app-affecting changes (bun run e2e, or bun run e2e:full when touching agent behavior)
• Before/after screenshots are included for frontend changes, or marked not applicable
• Relevant SPEC.md / top-level specs updated to reflect any boundary, contract, or behavior change
• I have read the Contributing guide and agree to the Code of Conduct

Testing notes:

• bun run lint and bun run typecheck passed (18/18 tasks) via the pre-commit hook. check:deps, check:boundaries and check:seams also passed.
• bun run test: 17/18 tasks pass. @thinkrail/server has 4 failures in src/changes/changes.test.ts (CRLF/final-newline cases). They reproduce identically on origin/main and are unrelated to this change.
• bun run e2e → all 8 shards passed. Before that, e2e/feedback.spec.ts was run on its own and passed.

[jetbrains-air]

Approved — ready to merge.