feat(leash): complete Phase 7 control plane

[Blockchain-Oracle]

Outcome

Implements the real Phase 7 Leash owner control plane:

• persistent Magic owner session and owner/merchant identity upgrade
• PostgreSQL-backed cap policy, four cycle modes, durable halt/reset, exact settled + pending + overage display
• tiered notifications with stable pagination, real unread state, destination novelty, and float-empty events
• owner-scoped Leash key issue/rotate lifecycle and runnable standalone/proxy MCP configuration
• resource URL redaction/canonicalization before network use

Verification

• pnpm lint
• pnpm check:showcase
• pnpm typecheck
• pnpm test (web 152 files / 676 tests; all monorepo tasks green)
• pnpm build (47 Next routes)
• pnpm --filter @tab/web db:check
• independent frontend verdict: PROCEED
• independent backend verdict: READY WITH WARNINGS

Honest boundaries

• B-03/B-04 money-moving surfaces remain blocked; no fake settlement, top-up, withdrawal, or rebalance state was added.
• Public leash-mcp package publication is still labeled pending.
• float_low emission remains deferred until a real watcher and threshold exist.
• Source files stay below the 300-line hard cap; several critical modules remain above the 200-line review target and are recorded as non-blocking cleanup.
• Zen walkthrough is pending only because the Mac is locked; PostgreSQL, CLI, render, interaction, build, and API checks are real.

[gitguardian]

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