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/post-compromise-security.md

@@ -13,7 +13,7 @@ PCS is the complement of [forward secrecy](forward-secrecy.md):
 - **Post-compromise security** protects the **future** from a past compromise.
 
 MLS (RFC 9420) is specifically designed to provide both properties simultaneously
-for group messaging. This is a key differentiator of quicproquo's design.
+for group messaging. This is a key differentiator of quicprochat's design.
 
 ## How MLS Provides PCS
 
@@ -64,7 +64,7 @@ This means:
 For a group of 1,000 members, the path length is approximately 10 nodes --
 making PCS practical even for large groups.
 
-## Epoch Advancement in quicproquo
+## Epoch Advancement in quicprochat
 
 In the current implementation, epoch advancement occurs through the `GroupMember`
 methods in `group.rs`:
@@ -145,7 +145,7 @@ deleted), and future epochs are protected by PCS (new key material generated).
 
 Signal's group messaging uses **Sender Keys**, a fundamentally different
 mechanism from MLS's ratchet tree. The comparison is instructive because it
-highlights why MLS was chosen for quicproquo:
+highlights why MLS was chosen for quicprochat:
 
 ### Signal Sender Keys
 
@@ -168,7 +168,7 @@ security. If an attacker compromises a member's Sender Key:
   membership changes.
 - There is no automatic healing mechanism analogous to MLS's ratchet tree.
 
-### MLS Ratchet Tree (quicproquo)
+### MLS Ratchet Tree (quicprochat)
 
 In contrast, MLS's ratchet tree provides PCS because:
 
@@ -218,7 +218,7 @@ periodic Updates (planned) will bound the healing window.
 
 ### Server compromise does not prevent PCS
 
-The quicproquo server is MLS-unaware -- it stores and forwards encrypted
+The quicprochat server is MLS-unaware -- it stores and forwards encrypted
 MLS messages without access to the group state. A compromised server cannot:
 
 - Prevent PCS by blocking Commits (it could perform denial-of-service, but