#20865 web: fix the feat-cmux-next web test base reds (no bead)

Fixes the three web/ unit-test reds on feat-cmux-next that block every PR running the web shards (for example #20854).

Summary

• web/scripts/devbox-image-common.ts: the main sync (0ee3754ec494) brought #20524's freestyle-cmux-devbox-agents-1014b ladder, baked from main's devbox sources. feat-cmux-next still carries its own desktop source changes (cx-6so.49 L1, the metadata service), so the DEVBOX_AWAITING_REBAKE entry from #19553 now names that bake (f221dae31c12) and feat's current digest (c6bdea67d318). The comment says to move both on a main sync that brings a new ladder.
• web/tests/teams-accept.test.ts: "omits the publishable key headers when none is configured" still expected x-stack-project-id, which #20236 replaced with x-hexclave-project-id (the client and its sibling test already use the Hexclave names).

Verification

• Red: Web tests (1/4) and (2/4) on #20854 at base 058e915ac419 (checked-in image manifest x2, Stack invitation-code client).
• Green: bun test tests/vm-image-manifest.test.ts tests/teams-accept.test.ts on the Linux builder: 35 pass, 0 fail.
• bun run lint:complexity (web/AGENTS.md): 39 findings matched the baseline, none new. No devbox template, bake script or running-machine code changes; the excuse stays exact (one baked digest against one current digest), and the real fix is the rebake that deletes it.
• changelog patch notes cards > the latest documented release says how to try each feature, red on main too: the v0.65.2 card shipped without tryIt lines. Added one per feature (cmux login and cmux vm restart <machine> checked against main's CLI). bun test of the three files on the builder: 49 pass, 0 fail.

Changelog

none

🤖 Generated with Claude Code

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Summary by cubic

Fixes three web/ unit-test reds on feat-cmux-next that block every PR running the web shards (e.g. #20854).

• devbox-image-common.ts: the awaiting-rebake entry now names #20524's freestyle-cmux-devbox-agents-1014b ladder bake and feat's current digest.
• teams-accept.test.ts: expects x-hexclave-project-id, which #20236 replaced x-stack-project-id with.
• changelog-media.ts: v0.65.2's changelog cards shipped without the tryIt lines the latest-release test requires; added one per feature (cmux login, cmux vm restart <machine>).