Remove Graph code from mail-inbox and verify the dependency is gone

[jbagsik]

Parent

#1

What to build

The contract step of expand–contract: delete the old form now that nothing calls it.

Remove the Graph service, the Graph exception classes, the Graph client factory and the Graph-shaped page wrapper from moox/mail-inbox, along with the Graph credential keys in its configuration. Drop the Microsoft dependency from its composer.json.

The proof that this ticket is done is not "the tests pass" — it is that a fresh install of moox/mail-inbox alone pulls no Microsoft code, and that its suite still runs green on the in-memory fake driver.

Acceptance criteria

• moox/mail-inbox contains no Graph or Microsoft class references anywhere, including in comments and config keys
• Its composer.json requires no Microsoft package
• A clean install of the package alone resolves without any Microsoft dependency in the lock file
• Its full suite passes against the in-memory fake driver, with no network access
• The immutable-identifier middleware is verifiably still active in moox/msgraph — this is the regression most likely to slip through, so it needs its own assertion
• README, CHANGELOG and the package glossary describe a transport-neutral package; no leftover text claims Microsoft Graph

Blocked by

• Migrate mail-inbox jobs to the driver and add the driver column #5 — the domain package must already run on the contract
• Move consumer type hints and the ignored-folder config off Graph #6 — the consumer must be migrated before its dependency is removed