fix(xhttp): stop injecting scMaxEachPostBytes/scMinPostsIntervalMs defaults (#5141)

The panel seeded xhttp configs with scMaxEachPostBytes=1000000 and
scMinPostsIntervalMs=30 — xray-core''s own defaults — and emitted them
into every generated config and share link. The literal
scMinPostsIntervalMs=30 is a stable DPI fingerprint that Russia''s TSPU
keys on to block connections on mobile networks.

New configs no longer seed these values (empty schema/template defaults,
so xray-core applies its internal defaults). For configs already stored
with the old defaults, the link/subscription builders now drop values
equal to xray-core''s defaults instead of advertising them — covering
panel share links, the raw subscription, and the JSON subscription
without requiring every inbound to be re-saved. Non-default values the
user set deliberately are still emitted.

frontend/src/lib/xray/outbound-link-parser.ts

@@ -114,7 +114,7 @@ function buildStream(network: string, security: string): Raw {
     case 'xhttp':
       stream.xhttpSettings = {
         path: '/', host: '', mode: 'auto', headers: {},
-        xPaddingBytes: '100-1000', scMaxEachPostBytes: '1000000',
+        xPaddingBytes: '100-1000',
       };
       break;
     default: