🐛 fix: sub-step readability, erase_all workaround, error state

Fix 1 — SubStepFrame readability:
- FONT_BODY (12pt) instead of FONT_SMALL dots/labels
- Number-circle colored dots (CIRCLE_PENDING/RUNNING/COMPLETE/ERROR)
- Accent-colored labels matching StepHeader (ACCENT_*)
- Percentage label next to running phase name

Fix 2 — erase_all full-chip erase:
- Creates temp zero-filled file of flash capacity (from flash_model)
- Uses -erase_only with dummy file instead of failing -erase_all flag
- Supports s25fl256s1 (32MB) which lacks density info for -erase_all
- _flash_capacity() maps model name→bytes

Fix 3 — Error state:
- set_phase('error') shows ✗ red on all sub-steps
- Only shows 'done' (green ●) on actual success

Fix 4 — Style consistency:
- Sub-step colors match StepHeader: CIRCLE_*/ACCENT_*/SUCCESS/DANGER

config.yaml

@@ -1,7 +1,7 @@
 bootloader_bin_path: /home/ly0kos/work/Verify/FW/tftp_app/bootloader/bootloader_z100_800M.bin
 bootloader_bit_path: /home/ly0kos/work/Verify/FW/tftp_app/bootloader/pl_arm_wrapper_hw_platform_0/pl_arm_wrapper.bit
 bootloader_elf_path: /home/ly0kos/work/Verify/FW/tftp_app/bootloader/app.elf
-erase_before_program: true
+erase_all: true
 firmware_bin_path: /home/ly0kos/work/Verify/FW/V1.3.1.3.3_06_01_pmu_cpld_check/V1.3.1.3.3_06_01_pmu_cpld_check.bin
 flash_model: s25fl256s1
 flash_type: qspi-x4-single