refactor(arch): remove slop from the package-by-module and CW1004 work

[mforce]

Refs #1087
Refs #1116

Removes dead code and stale prose that the package-by-module work (#1089–#1099, #1119) and the CW1004 work (#1116) left behind. It also carries the credential-epoch sentence from #1127, which is closed in favour of this PR. Behaviour does not change.

What changed and why

Where	Change	Why
ModuleEdgeAnalyzer.Attribute, ModuleMap.Claimant	Attribution uses the namespace owner directly; Claimant is deleted	#1099 removed type claims, so _claims holds only namespaces. Claimant(symbol) could match only a type whose full name equals a claimed namespace, and no type in src/ does (all 904 type names checked against all 35 claims)
tools/module-move/move.py	marks command deleted	It strips [ModuleContract], which #1099 deleted; nothing is left to strip
Edge reasons in Common/Architecture/Modules/*.cs	Domain.Accounts.*, Domain.Catalog.EggUnit and Domain.Eggs.EggLot become "Farm's X", "Commerce's EggUnit" and "EggLot"	Those namespaces no longer exist. A module-qualified name points to the right type and stays true when a folder moves. No test reads reason text
Reasons, two test comments, src/AGENTS.md, decisions 514, 850 and 1023	"#1087 S8", "S9" and "S10" become #1095, #1097 and #1099	Slice ids live only in a plan; the PR numbers are what a reader can open. The mapping is taken from each PR's own body
AccessOwnershipClaimTests comment	"through a namespace claim, not a type claim" becomes "Access, not the Platform hub, owns them"	Type claims no longer exist
src/AGENTS.md, contract rule	"Finance, Farm, … and Insights are contracted today" becomes "Every module has a contract today"	The list left out Access, which has had a contract since #857. All eight modules have a Contracts/ folder
src/AGENTS.md, ledger rule	"Nine namespace owners (…)" becomes "Each namespace owner, every module and Platform,"	A hand-copied count goes stale when a module is added
Decision 849, #1087 amendment	One added sentence pointing to #1116's wider contract rule	The amendment says Domain contracts hold only enums and nested types are never contract; #1116 changed both
docs/architecture.md, epoch sentence (from #1127)	Names logout and the /error re-execution as exempt, and the unparseable-claim rejection	"Every authenticated request" was false; CredentialEpochFreshReadTests pins the exemptions

Considered and left unchanged:

• AdapterScope's two Concat helpers. The owner chose a single shared definition in feat(arch): CW1004, flag non-contract peer reach inside method bodies #1116.
• Decision 859's S1–S3. Those name [C] #514 slice 17: assembly split — conditional on Track A/B evidence #859's own slices, not refactor(arch): group code by module folder, with contracts in a Contracts folder #1087's.
• Em-dash comments shown in the moved files' diffs. They predate this work; the moves only carried them along.

Proof

Check	Result
dotnet build Cluckwork.slnx --no-incremental	0 warnings, 0 errors
Mutation: CreateExpenseHandler names Commerce's DiscountCeiling	build exit 1, error CW1001: undeclared cross-owner edge Finance -> Commerce
Mutation: CreateExpenseHandler names Flock Management's Flock	build exit 1, error CW1004: Finance … reaches FlockManagement's non-contract type …Flock
move.py marks	prints the usage text and exits; no command remains

Guard classes, each run on its own: ModuleEdgeAnalyzerTests 14, ModuleLedgerRealTreeTests 2, ModuleLedgerTests 41, AdapterReachRealTreeTests 2, AdapterReachTests 102, PeerContractRealTreeTests 1, PeerContractTests 10, AdapterTierRealTreeTests 3, CompatibilityExceptionRealTreeTests 2, CompatibilityExceptionTests 37, ContractDerivationTests 1, ModuleContractRealAssemblyTests 1, NamespaceFolderAgreementTests 10, AccessOwnershipClaimTests 2, SeamSurfaceRealAssemblyTests 2, CouplingMatrixRealTreeTests 3, TableOwnerRealModelTests 2, TenantBypassRealTreeTests 4 and TenancyDocsFreshnessTests 1 all pass. The SchemaDocsTests image-pin guards and CredentialEpochFreshReadTests pass 11/11 together.