fix(category): name a heuristic category only at blocking confidence

e19299e made the resolver's heuristic mappings reachable by reading the
raw signals. A refuting review showed the cost: aggressive mode blocks a
lone 50-point neighbor-spoof match, which also fires on local banks and
schools, and with Scam set to Allow that block became
category_policy:scam:allow and the call rang. The resolver's own trust
rule reserves a category for strong evidence, so the heuristic branch
now requires the score the default setting blocks at (60). Confident
blocks keep their category; the weak one stays a plain heuristic block.

Tests: CallCategoryResolverTest adds the aggressive-mode case (50 is
Unknown, 60 is Scam). Existing heuristic cases use 65 and 70 and are
unchanged.

Author: SysAdminDoc

CHANGELOG.md

@@ -43,7 +43,10 @@ All notable changes to CallShield will be documented in this file.
   campaign range as a robocall, and a toll-free one as a telemarketer, so
   the action you picked for that category applies. Those mappings existed
   but never matched, because they looked for internal names the block
-  description had already turned into plain words.
+  description had already turned into plain words. They only apply to a
+  block as confident as the default setting requires, so a lone
+  neighbor-spoof match that only aggressive mode blocks stays uncategorized
+  and no category rule can let it through.
 
 - CallShield starts faster when a call wakes it. Looking for an interrupted
   backup restore held the main thread about 0.7 seconds on every start

app/src/main/java/com/sysadmindoc/callshield/data/CallCategory.kt

@@ -39,6 +39,9 @@ enum class CallCategory(
 }
 
 object CallCategoryResolver {
+    /** The heuristic score the default setting blocks at; below it a signal is too weak to name a category. */
+    private const val HEURISTIC_CATEGORY_MIN_CONFIDENCE = 60
+
     /** Convenience overload for callers holding a persisted `BlockedCall`
      *  (which doesn't carry a SpamCheckResult type field but does carry
      *  matchReason, description, and confidence). */
@@ -117,8 +120,11 @@ object CallCategoryResolver {
         // Heuristic reasons: map the strongest signals. A live result carries
         // the raw tokens in `signals`; its description is display text in the
         // app language (and always had the underscores replaced), so it only
-        // helps callers that still pass tokens there.
-        if (result.reasonCode == BlockReasonCode.HEURISTIC) {
+        // helps callers that still pass tokens there. Only at the confidence
+        // the default setting blocks at: aggressive mode blocks on a single
+        // 50-point neighbor-spoof match, which also fires on local banks and
+        // schools, and naming that Scam would let a Scam rule decide it.
+        if (result.reasonCode == BlockReasonCode.HEURISTIC && result.confidence >= HEURISTIC_CATEGORY_MIN_CONFIDENCE) {
             val evidence = (result.signals + desc).joinToString(" ")
             when {
                 "wangiri" in evidence -> return CallCategory.Wangiri

app/src/test/java/com/sysadmindoc/callshield/data/CallCategoryResolverTest.kt

@@ -100,6 +100,19 @@ class CallCategoryResolverTest {
         assertEquals(CallCategory.Unknown, CallCategoryResolver.resolve(live("suspicious", "号码格式异常", "invalid_format")))
     }
 
+    @Test
+    fun `a weak heuristic block names no category, so no category rule can wave it through`() {
+        // Aggressive mode blocks a lone neighbor-spoof match at 50. With Scam
+        // set to Allow, naming it Scam let the call ring.
+        val weak =
+            BlockResult
+                .block("heuristic", type = "spoofed", description = "Possible neighbor spoofing", confidence = 50, signals = listOf("neighbor_spoof"))
+                .toSpamCheckResult()
+
+        assertEquals(CallCategory.Unknown, CallCategoryResolver.resolve(weak))
+        assertEquals(CallCategory.Scam, CallCategoryResolver.resolve(weak.copy(confidence = 60)))
+    }
+
     @Test
     fun `heuristic with rapid_fire resolves to Robocall`() {
         val result =