feat(text): add text leading trim

[kisvegabor]

Fixes #6131
Continues: #9743

I needed to generate all built-in fonts again, and the bitmaps are formatted differently (e.g. 0x7 -> 0x07) and also there are 1 bit differences in a few cases. I manually reverted the Montserrat 14 font's bitmaps to avoid having too many ref image changes, but in other fonts triggered some very small changes on some images.

@FASTSHIFT I also updated how static fonts are handled in VGLite.

This image show what this feature does:

Notes

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• Add Tests if applicable.
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[github-actions]

Hi 👋, thank you for your PR!

We've run benchmarks in an emulated environment. Here are the results:

ARM Emulated 32b - lv_conf_perf32b

Scene Name	Avg CPU (%)	Avg FPS	Avg Time (ms)	Render Time (ms)	Flush Time (ms)
All scenes avg.	27	37	7	7	0

Detailed Results Per Scene

Scene Name	Avg CPU (%)	Avg FPS	Avg Time (ms)	Render Time (ms)	Flush Time (ms)
Empty screen	11	33	0	0	0
Moving wallpaper	2	33	1	1	0
Single rectangle	0	50	0	0	0
Multiple rectangles	0	33	0	0	0
Multiple RGB images	0	39	0	0	0
Multiple ARGB images	11 (+1)	39 (-2)	3	3	0
Rotated ARGB images	54 (-1)	44	15	15	0
Multiple labels	6	35	0	0	0
Screen sized text	81 (+1)	45	17	17	0
Multiple arcs	40	33	7	7	0
Containers	3 (-1)	37	0	0	0
Containers with overlay	88 (+2)	21	44	44	0
Containers with opa	16 (-1)	36 (-1)	1	1	0
Containers with opa_layer	18	34	5	5	0
Containers with scrolling	45 (+1)	45	12	12	0
Widgets demo	70 (-2)	39 (-1)	16	16	0
All scenes avg.	27	37	7	7	0

ARM Emulated 64b - lv_conf_perf64b

Scene Name	Avg CPU (%)	Avg FPS	Avg Time (ms)	Render Time (ms)	Flush Time (ms)
All scenes avg.	25 (+1)	37	6	6	0

Detailed Results Per Scene

Scene Name	Avg CPU (%)	Avg FPS	Avg Time (ms)	Render Time (ms)	Flush Time (ms)
Empty screen	11	33	0	0	0
Moving wallpaper	1	33	0	0	0
Single rectangle	0	50	0	0	0
Multiple rectangles	0	35	0	0	0
Multiple RGB images	0	39	0	0	0
Multiple ARGB images	11	42	0	0	0
Rotated ARGB images	29	33	9	9	0
Multiple labels	2	35	0	0	0
Screen sized text	84	46	18	18	0
Multiple arcs	40 (+9)	33	6	6	0
Containers	4	37	0	0	0
Containers with overlay	89	22	42 (+1)	42 (+1)	0
Containers with opa	14	36 (-2)	0 (-1)	0 (-1)	0
Containers with opa_layer	7 (+1)	37 (+1)	1	1	0
Containers with scrolling	48 (+1)	48	12 (+1)	12 (+1)	0
Widgets demo	68 (+1)	40	15	15	0
All scenes avg.	25 (+1)	37	6	6	0

Disclaimer: These benchmarks were run in an emulated environment using QEMU with instruction counting mode.
The timing values represent relative performance metrics within this specific virtualized setup and should
not be interpreted as absolute real-world performance measurements. Values are deterministic and useful for
comparing different LVGL features and configurations, but may not correlate directly with performance on
physical hardware. The measurements are intended for comparative analysis only.

---

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[cubic-dev-ai]

2 issues found across 94 files

Note: This PR contains a large number of files. cubic only reviews up to 75 files per PR, so some files may not have been reviewed.

Prompt for AI agents (unresolved issues)

Check if these issues are valid — if so, understand the root cause of each and fix them. If appropriate, use sub-agents to investigate and fix each issue separately.


<file name="src/misc/lv_style_gen.h">

<violation number="1" location="src/misc/lv_style_gen.h:789">
P2: This header is generated by style_api_gen.py, so adding the new text leading trim API here will be overwritten. Please add the property to style_api_gen.py and regenerate the header instead.

(Based on your team's feedback about treating style_api_gen.py as the source of truth for lv_style_gen.h.) [FEEDBACK_USED]</violation>
</file>

<file name="src/widgets/label/lv_label.c">

<violation number="1" location="src/widgets/label/lv_label.c:852">
P2: Leading-trim draws text outside the object bounds (txt_coords y1/y2), but ext draw size still only uses `font_h/4`. If trims are larger than `font_h/4`, glyphs can be clipped. Update LV_EVENT_REFR_EXT_DRAW_SIZE to include the trim offsets when leading trim is enabled.</violation>
</file>

_{Reply with feedback, questions, or to request a fix. Tag @cubic-dev-ai to re-run a review.}

[FASTSHIFT]

Encapsulating it into a function makes it easier to understand, so why is this change necessary?

[kisvegabor]

I wanted to make it fallback to draw_buf creation in case of errors. I updated it.

[AndreCostaaa]

Can we move these right after line_height and base_line attributes to avoid padding bytes as much as possible?
The pointers below should also be moved to the top of the structure too but it's unrelated and can be done in a separate PR if you prefer