Let an e2e run test the working tree's front end (BL-16799)

[hatton]

A launched Bloom serves its React UI from the built output/browser, so an edit
to a .tsx file did not reach the suite until somebody rebuilt that bundle,
which AGENTS.md reserves for a developer or CI.

Set BLOOM_E2E_VITE_PORT= and fixtures/launchBloom.ts passes --vite-port
to the Bloom it launches, which then loads every React control from that dev
server. Bloom already had the option; nothing passed it.

Use 5173 and set the variable. The README, the add-e2e-test skill and the new
AUTOMATION-DEBT.md entry all say why: the page list and the toolbox write
http://localhost:5173 into their own imports, so on any other port those two
frames come up empty, which reads as the feature being missing; and an unset
variable does not mean "no dev server", because a dev build probes 5173 by
itself, so a run can quietly test a bundle from yesterday.

Adds two AUTOMATION-DEBT.md entries rather than retiring one: "Which front end
the e2e suite tests depends on what else is running", for the choice the
fixture still does not own, and "A Vite dev server only reaches the whole UI on
port 5173", for the two pug files that ignore the port.

Verified: type check clean. A full suite run against a dev server on the
working tree is what found both entries above.

This is one of eleven stacked pull requests (BL-16799)

Each one pays down one entry of src/BloomE2E/AUTOMATION-DEBT.md, and each branches off the one before it. Base: BL-16799-component-tests-in-ci. Review only this pull request's own commit; the ones below it are reviewed in their own pull requests. The first six change test and tooling code only; the last five also change product code.

1. BL-16799-automation-scripts — Make the bloom-automation scripts safe to ask for help
2. BL-16799-vr-collect-failures — Report every failed image comparison in a visual-regression case, not the first
3. BL-16799-component-tests-in-ci — Run the component-tester Playwright suites nightly
4. BL-16799-vite-port — Let an e2e run test the working tree's front end
5. BL-16799-type-in-one-call — Type into a text box in one call, not one key press per character
6. BL-16799-page-screenshot — Capture a whole book page from a test
7. BL-16799-toolbox-registration — Register the toolbox tools from one list both callers share
8. BL-16799-shell-document — Stop a test attaching to a shell document Bloom does not drive
9. BL-16799-tab-test-ids — Click a workspace tab by a test id, not by its localized label
10. BL-16799-page-change — Refuse a page change the Edit tab cannot do, and wait before asking
11. BL-16799-collection-languages — Set a collection's languages through an e2e hook, not by writing XML

Replaces #8276, which did all of this in one pull request.

Verification of the whole stack, at its tip: the C# suite passes (3338 passed, 13 skipped), the front-end vitest suite passes (781 passed, 5 skipped), and the src/BloomE2E suite passes against a Vite dev server on the working tree (36 passed, 0 skipped, 8.2 minutes). Each pull request also has its own type check and lint.

🤖 Generated with Claude Code

Devin review

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This change is 

[hatton]

[Claude Opus 5 from Hatton's machine during devin-review]

Consulted Devin on 2026-09-03 22:45 UTC up to commit 215d8123d70179961e58e153d416474048ffb713.