Minamp 1.4: faster connecting

- Remember the connection that worked and try it alone first next start
- Prefer plain HTTP on the home network (each TLS handshake costs seconds on a
  600 MHz phone); new setting "Encrypt at home too" to keep HTTPS
- Try secure addresses one at a time instead of in parallel, so they don't
  all time out together
- TLS 1.2 with session resumption: reconnects skip the full handshake
- Cache certificate chains already verified; changing the trusted roots
  clears that cache and all TLS sessions
- README: updated connection order; test: session resumption check and
  HandshakeProfile

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

src/com/minamp/net/Http.java

@@ -133,6 +133,12 @@ public final class Http {
         }
     }
 
+    /** Forget resumable TLS sessions (next connection to each host does a full, verified handshake). */
+    static void forgetSessions() {
+        synchronized (sessions) { sessions.clear(); }
+        evictAll();
+    }
+
     /** Drop all pooled connections (e.g. after the network changed). */
     public static void evictAll() {
         final List<Conn> doomed = new ArrayList<Conn>();
@@ -191,6 +197,8 @@ public final class Http {
         private final String host;
         private final String sessionKey;
 
+        private final long started = System.currentTimeMillis();
+
         Client(TlsCrypto crypto, String host, String sessionKey) {
             super(crypto);
             this.host = host;
@@ -209,6 +217,16 @@ public final class Http {
             return v;
         }
 
+        /**
+         * TLS 1.2 only: this TLS stack can resume 1.2 sessions but not 1.3 ones, and on a 600 MHz
+         * phone a resumed handshake (no key exchange, no signature checks) is the difference
+         * between ~10 s and well under a second for every new connection.
+         */
+        @Override
+        protected com.minamp.bc.tls.ProtocolVersion[] getSupportedVersions() {
+            return com.minamp.bc.tls.ProtocolVersion.TLSv12.only();
+        }
+
         @Override
         public TlsSession getSessionToResume() {
             synchronized (sessions) { return sessions.get(sessionKey); }
@@ -217,6 +235,9 @@ public final class Http {
         @Override
         public void notifyHandshakeComplete() throws IOException {
             super.notifyHandshakeComplete();
+            boolean resumed = context.getSecurityParametersConnection().isResumedSession();
+            DiagLog.log("TLS " + (resumed ? "resumed" : "full handshake") + " with " + host
+                    + " in " + (System.currentTimeMillis() - started) + "ms");
             TlsSession s = context.getSession();
             if (s != null && s.isResumable()) {
                 synchronized (sessions) { sessions.put(sessionKey, s); }