docs: audit links, glossary T0-T4, readability pass

Extend glossary with storage floors, source of truth, and linkable anchors.
Fix broken links, pose frame drift, rsync/offload wording, and README tone.
Add docs/improvement audit records and live demo links in design journey.

docs/05-network-security.md

@@ -23,9 +23,9 @@ graph TB
         A["drone A<br/>wg key + certs"]
         B["drone B<br/>wg key + certs"]
         C["drone C<br/>wg key + certs"]
-        A <-->|"WireGuard + mTLS"| B
-        B <-->|"WireGuard + mTLS"| C
-        A <-->|"WireGuard + mTLS"| C
+        A <-->|"WireGuard tunnel"| B
+        B <-->|"WireGuard tunnel"| C
+        A <-->|"WireGuard tunnel"| C
     end
     PROV -->|"per-device identity, peer list"| A
     PROV --> B
@@ -65,7 +65,7 @@ Keep both layers: WireGuard for *who is on the network and whether the wire is r
 ## Data at rest
 
 - On-board NVMe is encrypted (LUKS) with keys held in the device's secure element / TPM where the hardware provides one; the disk alone is unreadable.
-- The ground warehouse applies standard at-rest encryption plus role-based access; it is the single most valuable asset in the system (every flight ever flown).
+- The ground warehouse applies standard at-rest encryption plus role-based access; it is the [source of truth](00-glossary.md#source-of-truth) and the single most valuable asset in the system (every flight ever flown).
 
 ## Attack surface, deliberately shortened