clarify: rotation must optimize for PRIMARY label when multiple zones exist

Items often have multiple labels/zones at different orientations:
- Main label with part number, specs (PRIMARY)
- Vendor logos or small text (secondary)
- Barcodes at odd angles

Instruction: Always optimize rotation for the PRIMARY label (most text),
ignore secondary/vendor labels that conflict in orientation.

Examples added showing how to handle items with multiple label zones.

config/ai_prompt.md

@@ -92,12 +92,14 @@
 
   ### Rotation Analysis (CRITICAL - MAKE TEXT READABLE IN STANDARD ENGLISH)
   
-  **IMPORTANT: Photos may be at ANY angle. Your job: return the rotation angle to make the TEXT readable in standard English (horizontal, left-to-right, top-to-bottom).**
+  **IMPORTANT: Photos may be at ANY angle. Your job: return the rotation angle to make the PRIMARY LABEL TEXT readable in standard English (horizontal, left-to-right, top-to-bottom).**
   
-  **The image has EXIF orientation metadata stripped. Analyze it in its RAW/NATIVE state. Measure how much to rotate the image so that the PRIMARY label text reads normally.**
+  **The image has EXIF orientation metadata stripped. Analyze it in its RAW/NATIVE state. Measure how much to rotate the image so that the PRIMARY label (the one with the MOST text on the item) reads normally.**
+  
+  **PRIORITY: Focus on the MAIN/PRIMARY label** — ignore secondary labels, vendor logos, barcodes, or other small text zones that may be oriented differently. If multiple text zones conflict, optimize for the largest one.
   
   **Algorithm:**
-  1. Locate the PRIMARY text/label on the item (part number, manufacturer, specs)
+  1. Identify the PRIMARY text/label — the one with the MOST content (part number, manufacturer, specs, technical details)
   2. Determine the CURRENT orientation of that text:
      - Is it horizontal and readable left-to-right? → rotation needed: `0°`
      - Is it rotated 90° (vertical, pointing up)? → rotation to horizontal: `-90°` or `+90°` (depending on which way)
@@ -108,14 +110,16 @@
      - Negative value = clockwise rotation needed
   4. **Return any value in range -180° to +180°** (full circle allowed)
   
-  **Measurement examples** (make text readable left-to-right, top-to-bottom):
+  **Measurement examples** (make PRIMARY label text readable left-to-right, top-to-bottom):
-     - Text already reads normally horizontally → `0°`
+     - Primary text already reads normally horizontally → `0°`
-     - Text is vertical, pointing up (90° rotated) → `-90°` (rotate clockwise to make horizontal)
+     - Primary text is vertical, pointing up (90° rotated) → `-90°` (rotate clockwise to make horizontal)
-     - Text is vertical, pointing down (270° rotated) → `+90°` (rotate counter-clockwise)
+     - Primary text is vertical, pointing down (270° rotated) → `+90°` (rotate counter-clockwise)
-     - Text is upside-down (180° rotated) → `+180°` or `-180°` (rotate half-circle)
+     - Primary text is upside-down (180° rotated) → `+180°` or `-180°` (rotate half-circle)
-     - Text at 22° angle (tilted right) → `-22°` (rotate clockwise to level)
+     - Primary text at 22° angle (tilted right) → `-22°` (rotate clockwise to level)
-     - Text at -35° angle (tilted left) → `+35°` (rotate counter-clockwise to level)
+     - Primary text at -35° angle (tilted left) → `+35°` (rotate counter-clockwise to level)
-     - **No angle limit**: Photos may be taken at any angle. Return whatever rotation makes the label text readable in standard English orientation.
+     - **Multiple labels/zones**: Item has vendor logo at 90° AND main label at 0°. → return `0°` (optimize for PRIMARY/largest label, ignore vendor logo)
+     - **Barcode or small secondary text at odd angle**: Ignore it. Rotate to make PRIMARY label readable.
+     - **No angle limit**: Photos may be taken at any angle. Return whatever rotation makes the PRIMARY label text readable in standard English orientation.
 
   ### Confidence Score
   - Return `confidence`: 0.0-1.0 indicating reliability of crop/rotation analysis