chore: rename quicproquo → quicprochat in Rust workspace

Rename all crate directories, package names, binary names, proto
package/module paths, ALPN strings, env var prefixes, config filenames,
mDNS service names, and plugin ABI symbols from quicproquo/qpq to
quicprochat/qpc.

proto/qpc/v1/auth.proto

@@ -1,5 +1,5 @@
 syntax = "proto3";
-package qpq.v1;
+package qpc.v1;
 
 // OPAQUE registration + login (4 methods).
 // Method IDs: 100-103.

proto/qpc/v1/blob.proto

@@ -1,5 +1,5 @@
 syntax = "proto3";
-package qpq.v1;
+package qpc.v1;
 
 // Blob upload/download (2 methods).
 // Method IDs: 600-601.

proto/qpc/v1/channel.proto

@@ -1,5 +1,5 @@
 syntax = "proto3";
-package qpq.v1;
+package qpc.v1;
 
 // Channel create (1 method).
 // Method ID: 400.

proto/qpc/v1/common.proto

@@ -1,5 +1,5 @@
 syntax = "proto3";
-package qpq.v1;
+package qpc.v1;
 
 // Common types shared across services.
 

proto/qpc/v1/delivery.proto

@@ -1,5 +1,5 @@
 syntax = "proto3";
-package qpq.v1;
+package qpc.v1;
 
 // Delivery service: enqueue, fetch, peek, ack, batch (6 methods).
 // Method IDs: 200-205.

proto/qpc/v1/device.proto

@@ -1,5 +1,5 @@
 syntax = "proto3";
-package qpq.v1;
+package qpc.v1;
 
 // Device register/list/revoke (3 methods).
 // Method IDs: 700-702.

proto/qpc/v1/federation.proto

@@ -1,5 +1,5 @@
 syntax = "proto3";
-package qpq.v1;
+package qpc.v1;
 
 // Federation relay + proxy (6 methods).
 // Method IDs: 900-905.

proto/qpc/v1/group.proto

@@ -1,5 +1,5 @@
 syntax = "proto3";
-package qpq.v1;
+package qpc.v1;
 
 // Group management (4 methods).
 // Method IDs: 410-413.

proto/qpc/v1/keys.proto

@@ -1,5 +1,5 @@
 syntax = "proto3";
-package qpq.v1;
+package qpc.v1;
 
 // Key package + hybrid key CRUD (5 methods).
 // Method IDs: 300-304.

proto/qpc/v1/moderation.proto

@@ -1,5 +1,5 @@
 syntax = "proto3";
-package qpq.v1;
+package qpc.v1;
 
 // Moderation service: report, ban, unban, list reports, list banned.
 // Method IDs: 420-424.

proto/qpc/v1/p2p.proto

@@ -1,5 +1,5 @@
 syntax = "proto3";
-package qpq.v1;
+package qpc.v1;
 
 // P2P endpoint publish/resolve + health (3 methods).
 // Method IDs: 800-802.

proto/qpc/v1/push.proto

@@ -1,5 +1,5 @@
 syntax = "proto3";
-package qpq.v1;
+package qpc.v1;
 
 // Server-push event types (sent on QUIC uni-streams).
 // Event type IDs: 1000+.

proto/qpc/v1/recovery.proto

@@ -1,5 +1,5 @@
 syntax = "proto3";
-package qpq.v1;
+package qpc.v1;
 
 // Recovery service — encrypted recovery bundle storage.
 // Method IDs: 750-752.

proto/qpc/v1/user.proto

@@ -1,5 +1,5 @@
 syntax = "proto3";
-package qpq.v1;
+package qpc.v1;
 
 // User resolve + identity (2 methods).
 // Method IDs: 500-501.