chore: release v2.28.0

Bump version to 2.28.0, update changelog, and add Signal ID to the
GitHub Pages feature listing.

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

CHANGELOG.md

@@ -2,6 +2,16 @@
 
 All notable changes to iNTERCEPT will be documented in this file.
 
+## [2.28.0] - 2026-07-05
+
+### Added
+- **Signal ID** — Offline signal identification against a bundled 594-signal database (seeded from SigID Wiki via Artemis-DB). Match an unknown signal by frequency, bandwidth, and modulation; results are ranked 0–100 with match reasons and SigID Wiki links.
+- **Signal ID modal** — Standalone overlay (`SignalIdModal`) accessible from a new "Signal ID" button in the global nav Intel group, and from a dedicated "Identify Signal" button in the waterfall sidebar. Pre-populates from the current waterfall frequency when opened from there; accepts manual entry from the nav.
+- **`POST /signalid/match` route** — Scored matching API with 60-second in-process cache. Scores frequency centrality (40 pts), bandwidth match (30 pts), modulation match (20 pts), and region match (10 pts). Returns ranked matches with `match_reasons` annotations.
+- **`bin/import_artemis.py`** — One-command database refresh script. Downloads the latest Artemis-DB tar (~300 MB), extracts it, and merges new signals into `data/signals.json`. Run with `python3 bin/import_artemis.py --download`.
+
+---
+
 ## [2.27.0] - 2026-05-20
 
 ### Fixed

config.py

@@ -7,10 +7,20 @@ import os
 import sys
 
 # Application version
-VERSION = "2.27.0"
+VERSION = "2.28.0"
 
 # Changelog - latest release notes (shown on welcome screen)
 CHANGELOG = [
+    {
+        "version": "2.28.0",
+        "date": "July 2026",
+        "highlights": [
+            "Feat: Signal ID — offline signal identification against a bundled 594-signal database",
+            "Feat: Signal ID modal accessible from the global nav and waterfall sidebar",
+            "Feat: scored matching by frequency, bandwidth, modulation, and region (0–100)",
+            "Feat: import script (bin/import_artemis.py) to refresh database from Artemis-DB",
+        ],
+    },
     {
         "version": "2.27.0",
         "date": "May 2026",

docs/index.html

@@ -97,6 +97,11 @@
                         <h3>CW/Morse Decoder</h3>
                         <p>Morse code decoding with custom Goertzel tone detection for CW and OOK/AM envelope detection for ISM band signals.</p>
                     </div>
+                    <div class="feature-card" data-category="intel">
+                        <div class="feature-icon"><svg viewBox="0 0 24 24" fill="none" stroke="currentColor" stroke-width="1.5" stroke-linecap="round" stroke-linejoin="round"><circle cx="11" cy="11" r="8"/><line x1="21" y1="21" x2="16.65" y2="16.65"/><line x1="11" y1="8" x2="11" y2="14"/><line x1="8" y1="11" x2="14" y2="11"/></svg></div>
+                        <h3>Signal ID</h3>
+                        <p>Identify unknown signals offline against a bundled 594-signal database. Scored matching by frequency, bandwidth, and modulation with SigID Wiki references.</p>
+                    </div>
                     <div class="feature-card" data-category="intel">
                         <div class="feature-icon"><svg viewBox="0 0 24 24" fill="none" stroke="currentColor" stroke-width="1.5" stroke-linecap="round" stroke-linejoin="round"><circle cx="12" cy="12" r="10"/><line x1="2" y1="12" x2="22" y2="12"/><path d="M12 2a15.3 15.3 0 0 1 4 10 15.3 15.3 0 0 1-4 10 15.3 15.3 0 0 1-4-10 15.3 15.3 0 0 1 4-10z"/></svg></div>
                         <h3>WebSDR</h3>