feat(sites): add bilibili dynamic support (images and animated images)

Fetch `t.bilibili.com/<id>`, `www.bilibili.com/opus/<id>`,
`t.bilibili.com/h5/dynamic/detail/<id>` and `m.bilibili.com/dynamic/<id>`
through the anonymous `/x/polymer/web-dynamic/v1/detail` endpoint (no
cookie, no WBI signature; the site adds the device cookies
`/x/frontend/finger/spi` hands out, which is what lifts bilibili's
`-352` risk control).

Media: the `major.draw` grid (`.gif` sources become animations, the rest
photos with a downscaled `@518w.jpg` thumbnail used both as preview and
as the oversized fallback), an attached video's cover, and the quoted
dynamic's media for forwards. The video stream itself is not resolved;
`b23.tv` short links stay unmatched (they mostly point at videos, so
matching them would turn a silently ignored link into a failure reply).

`-352`/`-412` map to a retryable error so the queue backs off instead of
dropping the post; a removed dynamic (`500`) is permanent.

Registry-driven, so no bot-side code changes beyond the site lists in the
command replies; found while researching nazurin and
telegram-bili-feed-helper (see BILIBILI_PLAN.md).

crates/xmedia-bot/src/config.rs

@@ -1,5 +1,6 @@
 //! Central env handling. The only other places that read env are
-//! `Bot::from_env` (TELOXIDE_TOKEN) and x-media (PIXIV_REFRESH_TOKEN).
+//! `Bot::from_env` (TELOXIDE_TOKEN) and x-media (PIXIV_REFRESH_TOKEN,
+//! TWITTER_AUTH_TOKEN, BILIBILI_COOKIE).
 
 use std::env;
 use std::net::IpAddr;

crates/xmedia-bot/src/handlers/commands.rs

@@ -279,7 +279,7 @@ pub(crate) async fn execute_command(
                     bot,
                     message.chat.id.0,
                     message.id,
-                    "Unknown site. Use twitter, bsky, pixiv or misskey.",
+                    "Unknown site. Use twitter, bsky, pixiv, misskey or bilibili.",
                 )
                 .await?;
                 return Ok(());
@@ -320,7 +320,7 @@ pub(crate) async fn execute_command(
                             bot,
                             message.chat.id.0,
                             message.id,
-                            "Unrecognized link. Use a twitter/x, pixiv, bsky or misskey post URL.",
+                            "Unrecognized link. Use a twitter/x, pixiv, bsky, misskey or bilibili post URL.",
                         )
                         .await?;
                         return Ok(());
@@ -358,7 +358,7 @@ pub(crate) async fn execute_command(
                     bot,
                     message.chat.id.0,
                     message.id,
-                    "No enabled site matches this link (twitter/x, pixiv, bsky or misskey).",
+                    "No enabled site matches this link (twitter/x, pixiv, bsky, misskey or bilibili).",
                 )
                 .await?;
                 return Ok(());
@@ -400,7 +400,7 @@ pub(crate) async fn execute_command(
                         bot,
                         message.chat.id.0,
                         message.id,
-                        "No enabled site matches this link (twitter/x, pixiv, bsky or misskey).",
+                        "No enabled site matches this link (twitter/x, pixiv, bsky, misskey or bilibili).",
                     )
                     .await?;
                 }

crates/xmedia-bot/src/handlers/mod.rs

@@ -60,8 +60,8 @@ pub(crate) async fn reply_html(
 
 /// Log prefix tying the whole lifecycle of one link (fetch → send → cache →
 /// forward) together: the normalized cache key (`twitter:123…`, `pixiv:123`,
-/// `bsky:handle/rkey`) instead of the raw URL, so logs stay short and do not
-/// echo full user-submitted URLs at info level.
+/// `bsky:handle/rkey`, `bilibili:123…`) instead of the raw URL, so logs stay
+/// short and do not echo full user-submitted URLs at info level.
 pub fn log_key(url: &str) -> String {
     x_media::site::cache_key(url).unwrap_or_else(|| "<unsupported>".to_string())
 }

crates/xmedia-bot/src/state.rs

@@ -17,7 +17,7 @@ pub struct ChatData {
     pub edit_message: HashMap<i64, EditMessage>,
     /// name -> HTML template containing "[]"
     pub template: HashMap<String, String>,
-    /// site name (twitter/bsky/misskey/pixiv) -> user-supplied caption format
+    /// site name (twitter/bsky/misskey/pixiv/bilibili) -> user-supplied caption format
     /// with {url} {author} {author_url} {title} {tags} placeholders.
     pub message_format: HashMap<String, String>,
 }