doxygen: group name all in lowcase (part 2)

[unicornx]

group 的名字全部统一采用小写。这个 PR 是对 #10432 的继续。

本 PR 只是对注释进行改动，不涉及参与编译的代码。

本 PR 包含三个 commit，分别是对 fs，drivers，和 signal 部分的修改。

[github-actions]

📌 Code Review Assignment

🏷️ Tag: components

Reviewers: @Maihuanyi

Changed Files (Click to expand)

• components/dfs/dfs_v1/src/dfs.c
• components/dfs/dfs_v1/src/dfs_file.c
• components/dfs/dfs_v1/src/dfs_fs.c
• components/dfs/dfs_v1/src/dfs_posix.c
• components/dfs/dfs_v2/src/dfs.c
• components/dfs/dfs_v2/src/dfs_fs.c
• components/dfs/dfs_v2/src/dfs_posix.c
• components/drivers/audio/dev_audio.c
• components/drivers/include/drivers/adc.h
• components/drivers/include/drivers/dac.h
• components/drivers/include/drivers/dev_audio.h
• components/drivers/include/drivers/dev_can.h
• components/drivers/include/drivers/dev_i2c.h
• components/drivers/include/drivers/dev_pin.h
• components/drivers/include/drivers/dev_pwm.h
• components/drivers/include/drivers/dev_rtc.h
• components/drivers/include/drivers/dev_serial.h
• components/drivers/include/drivers/dev_serial_v2.h
• components/drivers/include/drivers/dev_spi.h
• components/drivers/include/drivers/dev_touch.h

🏷️ Tag: documentation

Reviewers: @CXSforHPU @GorrayLi @lianux-mm @unicornx

Changed Files (Click to expand)

• documentation/0.doxygen/components/filesystem.h
• documentation/0.doxygen/core/ipc.h
• documentation/6.components/device-driver/audio/audio.md

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📊 Current Review Status (Last Updated: 2025-07-23 06:41 CST)

• ⌛ @CXSforHPU Pending Review
• ⌛ @GorrayLi Pending Review
• ⌛ @Maihuanyi Pending Review
• ⌛ @lianux-mm Pending Review
• ⌛ @unicornx Pending Review

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