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/identity-keys.md

@@ -1,11 +1,11 @@
 # Ed25519 Identity Keys
 
 The Ed25519 identity keypair is the long-term cryptographic identity of a
-quicproquo client. It is generated once, persisted across sessions, and used
+quicprochat client. It is generated once, persisted across sessions, and used
 for MLS credential signing, Authentication Service registration, and delivery
 queue addressing.
 
-**Source:** `crates/quicproquo-core/src/identity.rs`
+**Source:** `crates/quicprochat-core/src/identity.rs`
 
 ## Structure
 
@@ -37,7 +37,7 @@ A fresh identity keypair is generated from the OS CSPRNG (`OsRng`) via
 `ed25519-dalek`:
 
 ```rust
-use quicproquo_core::identity::IdentityKeypair;
+use quicprochat_core::identity::IdentityKeypair;
 
 let identity = IdentityKeypair::generate();
 // The signing key seed is generated from OsRng (getrandom on Linux).