Address PR review: subtract-1 encoding and clamp max_hops

- Change > to >= so stored value 1 means direct/0-hop only (liamcottle)
- Clamp max_hops to 63 on write since getPathHashCount() caps at 63 (robekl)
- Update comments to reflect encoding: 0=no limit, 1=direct only, N=up to N-1 hops

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

src/helpers/BaseChatMesh.cpp

@@ -141,9 +141,9 @@ void BaseChatMesh::onAdvertRecv(mesh::Packet* packet, const mesh::Identity& id,
       return;
     }
 
-    // check hop limit for new contacts (0 = no limit)
+    // check hop limit for new contacts (0 = no limit, 1 = direct only, N = up to N-1 hops)
     uint8_t max_hops = getAutoAddMaxHops();
-    if (max_hops > 0 && packet->getPathHashCount() > max_hops) {
+    if (max_hops > 0 && packet->getPathHashCount() >= max_hops) {
       ContactInfo ci;
       populateContactFromAdvert(ci, id, parser, timestamp);
       onDiscoveredContact(ci, true, packet->path_len, packet->path);       // let UI know

src/helpers/BaseChatMesh.h

@@ -98,7 +98,7 @@ protected:
   virtual bool shouldAutoAddContactType(uint8_t type) const { return true; }
   virtual void onContactsFull() {};
   virtual bool shouldOverwriteWhenFull() const { return false; }
-  virtual uint8_t getAutoAddMaxHops() const { return 0; }  // 0 = no limit, 1-63 = max hops for auto-add
+  virtual uint8_t getAutoAddMaxHops() const { return 0; }  // 0 = no limit, 1 = direct only, N = up to N-1 hops
   virtual void onContactOverwrite(const uint8_t* pub_key) {};
   virtual void onDiscoveredContact(ContactInfo& contact, bool is_new, uint8_t path_len, const uint8_t* path) = 0;
   virtual ContactInfo* processAck(const uint8_t *data) = 0;