Fix documentation defects found by an adversarial review

Fifteen findings, all verified before acting. The ones that mattered:

- Corrections added without updating what they corrected. §5's table still
  said a cap-less NURI is one "without :k:", two hundred lines after §4
  established the discriminant is `r:`. Same shape of defect in the P1a
  report, which kept the sentence "it is the owner's keyring, upstream the
  keyring is the wallet" — the exact sentence §4quater declares wrong, and the
  one that produced a global in-memory keyring.

- A wrong source citation: RootCapRefresh/BranchCapRefresh live in
  verifier/src/commits/mod.rs, not repo/src/commit.rs, and are no-op stubs.

- Documentation describing deleted code: isolation.ts, discovery.readIndex,
  the global index, and an acceptance test that was dropped with discovery.

- The P1a implementation report had aged into being wrong in four places
  (caps not persisted, inbox processing not started, plain string types, the
  :k: segment). It is dated, so it now carries a header saying what later lots
  overtook, rather than being rewritten.

- vision.md stated "a document's data is stored encrypted" in the present
  tense. That is the target; here the cap value is the constant OK and nothing
  is encrypted. Said plainly now.

- Prose left mangled by an earlier mechanical find-and-replace, in four places
  I had claimed were repaired.

Also: reach.ts and connect.ts had no home in the permanent docs — the boundary
and the connection sequence are now described in simulation.md, not only in a
brief.

packages/client/docs/sdk-reference.md

@@ -92,6 +92,9 @@ useShape<T extends BaseType>(
 - `shape` — the ORM shape type (generated from a SHEX shape). Names the entity type
   and the properties to materialize.
 - `scope` — where to read: a `{ graphs, subjects }` scope object or a NURI string.
+  **Not to be confused with this library's `Scope`** (`types.ts`), which is the
+  literal union `public | protected | private` naming a store. Same word, two
+  meanings: the ORM's is a read target, ours is a placement.
   `undefined` yields an empty read.
 - **Returns** a `DeepSignalSet<T>` — a **live reactive set**. Iterate it like a set;
   the component re-renders whenever the set changes.