chore: rename quicproquo → quicprochat in docs, Docker, CI, and packaging

Rename all project references from quicproquo/qpq to quicprochat/qpc
across documentation, Docker configuration, CI workflows, packaging
scripts, operational configs, and build tooling.

- Docker: crate paths, binary names, user/group, data dirs, env vars
- CI: workflow crate references, binary names, artifact names
- Docs: all markdown files under docs/, SDK READMEs, book.toml
- Packaging: OpenWrt Makefile, init script, UCI config (file renames)
- Scripts: justfile, dev-shell, screenshot, cross-compile, ai_team
- Operations: Prometheus config, alert rules, Grafana dashboard
- Config: .env.example (QPQ_* → QPC_*), CODEOWNERS paths
- Top-level: README, CONTRIBUTING, ROADMAP, CLAUDE.md

docs/src/cryptography/forward-secrecy.md

@@ -6,7 +6,7 @@ compromised, past session keys cannot be recovered.** In other words, an
 attacker who obtains today's long-term key cannot use it to decrypt messages
 recorded yesterday.
 
-quicproquo provides forward secrecy at two independent layers: the transport
+quicprochat provides forward secrecy at two independent layers: the transport
 layer and the application layer. Even if one layer's FS mechanism is defeated,
 the other continues to protect message confidentiality.
 
@@ -28,7 +28,7 @@ In each TLS 1.3 handshake:
 
 Because the ephemeral keys exist only for the duration of the handshake,
 compromising the server's long-term TLS certificate key (currently self-signed
-in quicproquo) does not reveal past session keys.
+in quicprochat) does not reveal past session keys.
 
 ## Application Layer Forward Secrecy
 
@@ -54,7 +54,7 @@ This deletion is the mechanism that provides forward secrecy: once old epoch
 keys are erased, messages encrypted under those keys cannot be decrypted, even
 if the current group state is compromised.
 
-In quicproquo, epoch advancement occurs when:
+In quicprochat, epoch advancement occurs when:
 
 - `add_member()` is called, which creates a Commit and calls
   `merge_pending_commit()`.
@@ -91,7 +91,7 @@ HPKE init keys.
 
 ## Layered Forward Secrecy
 
-A distinctive property of quicproquo's design is that forward secrecy
+A distinctive property of quicprochat's design is that forward secrecy
 operates at two independent layers:
 
 ```text
@@ -135,7 +135,7 @@ unless they also break the transport encryption.
 Signal's Double Ratchet protocol also provides forward secrecy, but the
 mechanisms differ:
 
-| Property | Signal Double Ratchet | MLS (quicproquo) |
+| Property | Signal Double Ratchet | MLS (quicprochat) |
 |----------|----------------------|---------------------|
 | Scope | Pairwise (1:1 sessions) | Group (n-party) |
 | Ratchet granularity | Per message (symmetric ratchet) + per DH round (DH ratchet) | Per epoch (Commit) |