feat: Implement OLED display support and custom icons for 128x32 displays

- Added OLED functionality in keymap.c with custom rendering for layers and modifiers.
- Created a Python script to generate simple icons for OLED displays.
- Introduced a new rules.mk file to enable OLED features for the keymap.
- Developed an OLED font helper script for visualizing and designing custom graphics.
- Redesigned OLED layout to fit 128x32 displays, optimizing space for logos and layer indicators.
- Implemented flow tap functionality in flow_tap.c for enhanced key responsiveness.

OLED_FIX_README.md

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+# OLED Display Fix for 128x32 Screens
+
+## Problem
+Your OLED code was designed for larger displays (128x64) with 8 rows. Your 128x32 display only has **4 rows × 21 characters**, so the 3-row tall graphics take up most of the screen, leaving no room for useful information.
+
+## Solution Overview
+1. **Simplify graphics**: Use 1-row tall icons (single character height) instead of 3-row tall graphics
+2. **Optimize layout**: Better use of the 4 available rows
+3. **Update font file**: Replace oversized graphics with compact, readable icons
+
+## New Layout for 128x32 (4 rows)
+```
+Row 1: [Logo] LAYER NAME
+Row 2: [Icon] W-C-S  (modifiers)
+Row 3: WPM:045
+Row 4: CAPS  SCRL
+```
+
+## Files Modified
+
+### 1. OLED Code (keymap.c)
+Replace your current OLED functions with the compact version in:
+- `oled_redesign_128x32.c` (reference implementation)
+
+Key changes:
+- **Logo**: 2 characters instead of 15 (3×5 grid)
+- **Layer indicators**: 2 characters instead of 15 (3×5 grid)
+- **Modifiers**: 4 single characters (W-A-C-S) instead of multi-char graphics
+- **Text-based layer names**: More readable than icons
+- **Efficient spacing**: Uses all 4 rows effectively
+
+### 2. Font File (glcdfont.c)
+Update these character positions with simple icons:
+
+```c
+// 0x80-0x81: Logo (2 chars)
+0x3E, 0x41, 0x55, 0x55, 0x41, 0x3E,   // 0x80: Keyboard icon
+0x3E, 0x41, 0x55, 0x55, 0x41, 0x3E,   // 0x81: Keyboard icon
+
+// 0x92-0x93: Default layer (2 chars)
+0x08, 0x1C, 0x3E, 0x7F, 0x2A, 0x2A,   // 0x92: Home icon
+0x10, 0x38, 0x7C, 0xFE, 0x54, 0x54,   // 0x93: Home icon
+
+// 0x94-0x95: Symbol layer (2 chars)
+0x24, 0x7F, 0x24, 0x7F, 0x24, 0x00,   // 0x94: # symbol
+0x24, 0x2A, 0x7F, 0x2A, 0x12, 0x00,   // 0x95: $ symbol
+
+// 0x96-0x97: Navigation layer (2 chars)
+0x08, 0x1C, 0x2A, 0x08, 0x08, 0x08,   // 0x96: Up arrow
+0x08, 0x08, 0x08, 0x2A, 0x1C, 0x08,   // 0x97: Down arrow
+
+// 0x98-0x9B: Modifier keys (1 char each)
+0x66, 0x66, 0x00, 0x7E, 0x66, 0x66,   // 0x98: GUI/Windows
+0x7E, 0x09, 0x09, 0x09, 0x7E, 0x00,   // 0x99: ALT
+0x3E, 0x41, 0x41, 0x41, 0x22, 0x00,   // 0x9A: CTRL
+0x08, 0x1C, 0x2A, 0x08, 0x08, 0x08,   // 0x9B: SHIFT (arrow)
+```
+
+## Implementation Steps
+
+### Step 1: Update keymap.c OLED functions
+Copy the redesigned functions from `oled_redesign_128x32.c` to your `keymap.c`, replacing these functions:
+- `render_logo()` → `render_logo_compact()`
+- `render_logo2()` → (merged into main function)
+- `render_layer_state()` → `render_layer_name()` + `render_layer_icon()`
+- `render_mod_status_gui_alt()` → `render_modifiers_compact()`
+- `render_mod_status_ctrl_shift()` → (merged into modifiers_compact)
+- `render_status_main()` → `render_status_compact()`
+- `render_status_secondary()` → (use same compact function)
+- `oled_task_user()` → Updated version
+
+### Step 2: Update glcdfont.c
+1. Find line ~136 where character 0x80 starts
+2. Replace the hex values for characters 0x80, 0x81, 0x92-0x9B
+3. Keep all other characters (0x00-0x7F for ASCII text)
+
+### Step 3: Compile and Test
+```bash
+cd qmk_userspace
+bash build_all.sh
+```
+
+### Step 4: Flash to Keyboard
+Flash the `.uf2` files to both halves of your split keyboard.
+
+## Customization
+
+### Design Your Own Icons
+1. Visit: https://helixfonteditor.netlify.com/
+2. Each character is **6 pixels wide × 8 pixels tall**
+3. Export as hex array (6 bytes per character)
+4. Copy hex values to glcdfont.c
+
+### Character Format
+Each character = 6 bytes (one per column):
+```
+Byte format (binary): 0bDCBA9876
+where 0 = top pixel, 7 = bottom pixel
+
+Example (arrow up):
+   ▄     ▄▄▄  ▄ █ ▄   ▄      ▄      ▄   
+   █     ███  █ █ █   █      █      █   
+= [0x08, 0x1C, 0x2A, 0x08, 0x08, 0x08]
+```
+
+### Alternative: Use Text Instead of Icons
+If you prefer text-only (no custom graphics):
+```c
+// In render_modifiers_compact():
+if(modifiers & MOD_MASK_GUI)   oled_write_P(PSTR("W"), false);
+if(modifiers & MOD_MASK_ALT)   oled_write_P(PSTR("A"), false);
+if(modifiers & MOD_MASK_CTRL)  oled_write_P(PSTR("C"), false);
+if(modifiers & MOD_MASK_SHIFT) oled_write_P(PSTR("S"), false);
+```
+
+## Benefits of This Design
+
+✅ **Readable**: Text layer names are clearer than multi-row icons
+✅ **Efficient**: Uses all 4 rows with no wasted space
+✅ **Informative**: Shows layer, modifiers, WPM, and caps/scroll lock
+✅ **Compact**: Small icons fit in single row (1 char tall)
+✅ **Consistent**: Same layout on both keyboard halves
+✅ **Maintainable**: Simpler code, easier to modify
+
+## Tools Provided
+
+1. **oled_font_helper.py**: Visualize current font graphics
+2. **generate_simple_icons.py**: Generate simple icon hex values
+3. **oled_redesign_128x32.c**: Complete redesigned OLED code
+
+## Next Steps
+
+Would you like me to:
+1. Apply these changes directly to your keymap.c and glcdfont.c?
+2. Create a different layout design?
+3. Design custom icons for specific purposes?
+4. Keep some of your original graphics but optimize them?
+
+Let me know how you'd like to proceed!