fix(inbox): keep detail back link pointing at the tab you came from

[rafaeelaudibert]

Problem

After archiving a report while viewing it, the back button flipped from "Back to reports" to "Back to archive". The usual flow is: open Reports → open a report → maybe archive → go back. So you'd expect to land back in Reports, not Archive.

This wasn't a label being swapped — the architecture flips it implicitly. Archiving sets the report's status to suppressed, and InboxReportDetailGate redirects (replace: true) from /code/inbox/reports/$reportId to /code/inbox/dismissed/$reportId. That route mounts DismissedReportDetail, which hard-codes backTo="/code/inbox/dismissed" / "Back to archive". So the back link followed the report's new state instead of the path you took in.

The redirect is load-bearing (it keeps archived reports off the triage view), so it's kept — but it now remembers where you came from.

Change

• New useInboxBackTarget hook — owns the InboxListRoute / InboxBackTarget types, augments TanStack Router's HistoryState with an inboxBackOrigin field, and resolves the back link from history state (validating the untyped state at the boundary), with a fallback.
• InboxReportDetailGate — stamps the origin ({ to, label }, always a pipeline route at that point) into navigation state on the to-Archive redirect. Gains optional display-only backLinkTo/backLinkLabel; backTo stays the route identity that drives the redirect and engagement tracking.
• DismissedReportDetail — reads the recorded origin and uses it for both the missing-shell link and the header link; defaults to "Back to archive".
• InboxDetailFrame — backTo widened to the shared InboxListRoute union.
• Unit test for the history-state validator.

Behavior

Path in	Back link
Reports → open → archive	Back to reports → Reports list
Pulls → open → archive	Back to pull requests
Runs → open → archive	Back to runs
Archive tab / deep link / refresh	Back to archive (fallback)

Verification

⚠️ I could not run pnpm typecheck/tests locally — the sandbox's network is throttled to single-digit KiB/s and pnpm install gets OOM-killed before @tanstack/react-router and vitest are installed. Verified by manual review. Two things worth a CI/reviewer eye:

• The declare module "@tanstack/react-router" { interface HistoryState } augmentation (documented TanStack v1 pattern; mirrors the existing Register augmentation in router.ts).
• useLocation({ select }) typing.

🤖 Generated with Claude Code

[github-actions]

React Doctor found no issues in the changed files. 🎉

_{Reviewed by React Doctor for commit c7dd774.}

[greptile-apps]

_{Reviews (1): Last reviewed commit: "fix(inbox): keep detail back link pointi..." | Re-trigger Greptile}

[greptile-apps]

The four route strings are listed twice: once to build the InboxListRoute union and once to populate INBOX_LIST_ROUTES. Adding a fifth inbox list route requires touching both places. Using as const on a single array lets InboxListRoute be derived from it, keeping a single source of truth.

Suggested change

	const INBOX_LIST_ROUTES = new Set<InboxListRoute>([
	"/code/inbox/pulls",
	"/code/inbox/reports",
	"/code/inbox/runs",
	"/code/inbox/dismissed",
	]);
	const INBOX_LIST_ROUTE_VALUES = [
	"/code/inbox/pulls",
	"/code/inbox/reports",
	"/code/inbox/runs",
	"/code/inbox/dismissed",
	] as const;
	export type InboxListRoute = (typeof INBOX_LIST_ROUTE_VALUES)[number];
	const INBOX_LIST_ROUTES = new Set<InboxListRoute>(INBOX_LIST_ROUTE_VALUES);

Note: If this suggestion doesn't match your team's coding style, reply to this and let me know. I'll remember it for next time!

[rafaeelaudibert]

• fix(inbox): keep detail back link pointing at the tab you came from #2867 👈 (View in Graphite)
• main

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[github-actions]

Low-risk UI navigation fix: the new hook defensively validates history state, tests cover edge cases, and all changes stay within @posthog/ui with no architecture boundary crossings.

New commits pushed (delta classified non_linear_history) — stamphog approval dismissed; re-review running automatically.

[github-actions]

Focused inbox navigation fix entirely within @posthog/ui with proper defensive validation of untrusted history state, tests for edge cases, and no architecture violations. The greptile bot's outdated inline suggestion is already addressed in the current code.