A public, read-only web view of the directory (#215)

The directory renders its own pages from the store: the most subscribed, categories, A to Z,
search, and a page per feed with its address and a Copy button. No token, nothing that writes; /v1
keeps its token check. The publisher's HTML is shown as text, item links only when http(s), with
a strict Content-Security-Policy; covers load from their publishers with no referrer.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

crates/directory/Cargo.toml

@@ -8,6 +8,7 @@ name = "ipx-directory"
 path = "src/main.rs"
 
 [dependencies]
+ammonia.workspace = true
 anyhow.workspace = true
 axum.workspace = true
 clap.workspace = true
@@ -15,6 +16,7 @@ ipx-feed.workspace = true
 opentelemetry.workspace = true
 opentelemetry-otlp.workspace = true
 opentelemetry_sdk.workspace = true
+percent-encoding.workspace = true
 reqwest.workspace = true
 sea-orm.workspace = true
 serde.workspace = true