feat(scale): implement scale rollout with canary/blue-green/rolling strategies

[wjgong001]

Description

Replaces the scale rollout stub with a working implementation. Continuation of the scale command work (PRs #225 cost, #227 auto, #231 up, #232 dns+down).

What it does

• sh1pt scale rollout --version v2.1.0 --strategy canary --percent 10 — deploy to 10% of fleet
• sh1pt scale rollout --version v2.1.0 --strategy blue-green — parallel fleet, cut over atomically
• sh1pt scale rollout --version v2.1.0 --strategy rolling — replace in batches
• --dry-run to preview without modifying state
• --status to list all rollouts with their state (in-progress/completed/rolled-back/failed)
• --rollback <id> to revert a completed rollout
• --json for machine-readable output

Reads/writes same ~/.sh1pt/credentials.json fleet state as other scale commands. Rollout history persisted in ~/.sh1pt/rollouts.json.

Verification

• Typecheck: pnpm --filter @profullstack/sh1pt typecheck passes (exit 0)
• Same convention as PRs feat(scale): implement scale cost with real provider pricing data #225, feat(scale): implement scale auto with persistent rules #227, feat(scale): implement scale up with real fleet provisioning simulation #231, feat(scale): implement scale dns + scale down (DNS management + strategy-based teardown) #232 (TypeScript strict mode, same fleet state file)

Progress toward ugig gig

Replaces one more stub toward the "implement the 4 main sh1pt cli commands" goal.

[github-actions]

🤖 Auto-rebase: The branch was rebased successfully locally but could not be pushed to the fork. Please enable 'Allow edits from maintainers' in the PR settings, or rebase manually: git fetch upstream master && git rebase upstream/master.

[github-actions]

🤖 Auto-rebase: The branch was rebased successfully locally but could not be pushed to the fork. Please enable 'Allow edits from maintainers' in the PR settings, or rebase manually: git fetch upstream master && git rebase upstream/master.

[github-actions]

🤖 Auto-rebase: The branch was rebased successfully locally but could not be pushed to the fork. Please enable 'Allow edits from maintainers' in the PR settings, or rebase manually: git fetch upstream master && git rebase upstream/master.

[github-actions]

🤖 Auto-rebase: The branch was rebased successfully locally but could not be pushed to the fork. Please enable 'Allow edits from maintainers' in the PR settings, or rebase manually: git fetch upstream master && git rebase upstream/master.