fix(deploy): say a staged release is already installed when activating it

[dawsontoth]

⊙ Problem

The activate dialog said "Nothing is installed", and the staged detail said "with nothing to install". Both read as if activation does nothing. The point is the opposite: staging already did the install, so activating is quick and safe.

🤔 Is a copy-only change the right size, and is the positive framing right?

Yes, as asked. Three sentences change and no behavior does. The new copy says the install already happened instead of "nothing is installed". If the negation reads better, swapping it back is a one-line change. The "Stage only" help text and the already-live "nothing to activate" agree with the new copy, so they stay.

💡 Solution

• Activate dialog: "Everything was installed when this release was staged, so each node just switches to it."
• Roll back dialog: "Each node kept this release installed when it was replaced, so it just switches back."
• Both dialogs say "all nodes, which restart one at a time", fixing "every node, which restart".
• Staged detail: "Staged: built and installed, but not live. Activating it just switches each node to it."

Harper backs each claim. An activation swaps the staged build in "without resolving, fetching or installing anything", and a kept release is "a whole installed tree" (harper components/DESIGN.md).

Every string, before and after

Where	Before	After
Activate dialog	Nothing is installed: each node swaps in the release it staged.	Everything was installed when this release was staged, so each node just switches to it.
Roll back dialog	Nothing is installed: each node swaps back the copy it kept when this release was replaced.	Each node kept this release installed when it was replaced, so it just switches back.
Both dialogs	goes live on every node, which restart one at a time.	goes live on all nodes, which restart one at a time.
Staged detail	Activating it makes it live with nothing to install.	Activating it just switches each node to it.

✅ Verification

• New assertions pin each sentence: the activate dialog, the "Activate again" variant with its extra restart sentence, the staged detail and the roll back dialog. With the two components put back to stage's copy, all four tests fail.
• Gates on Node 24.21.0, exit codes captured: npx vitest run --maxWorkers=4 0 (533 files, 5,292 passed), npx tsc -b 0, npx oxlint --format stylish . 0, npx dprint check 0. The commit went through the pre-commit hook.
• Not checked in a browser. The tests render the real components.

🤖 Generated with Claude Code

Related PRs: #1943 overlaps (merged; this rewords the copy it shipped)
Complexity: easy

_{Review-Coverage: authored=claude; ran=codex,gemini,cursor-composer; adjudicated=domain; declined=cursor-grok,cursor-kimi,cursor-muse,muse; rounds=3; full=1 @ 95378e7}

_{Review-Attention: skim ~1m @ 95378e7}

[gemini-code-assist]

Code Review

This pull request updates the descriptive copy for activating and rolling back staged releases in both the UI components and their corresponding tests to make the behavior clearer. The review feedback suggests correcting a minor grammatical issue regarding subject-verb agreement where 'every node, which restart' should be updated to 'every node, which restarts' in two locations.

[github-actions]

Coverage Report

Status	Category	Percentage	Covered / Total
🔵	Lines	78.06%	13640 / 17472
🔵	Statements	78.01%	14479 / 18560
🔵	Functions	72.95%	3585 / 4914
🔵	Branches	73.03%	10743 / 14710

File Coverage

File	Stmts	Branches	Functions	Lines	Uncovered Lines
Changed Files
src/features/instance/config/deployments/components/ActivateStagedRelease.tsx	100%	92.5%	100%	100%
src/features/instance/config/deployments/components/StagedReleaseDetail.tsx	90%	89.28%	100%	87.5%	14-19

Generated in workflow #2340 for commit 95378e7 by the Vitest Coverage Report Action