[Bug] in-repo userspace code not included unless external userspace is also enabled

Describe the Bug

as a minimal test, i have a userspace dir users/ahihi containing only a config.h with #define RGB_MATRIX_TIMEOUT 5000. i am building with qmk flash -kb kprepublic/bm40hsrgb/rev2 -km ahihi -c, hoping for the userspace config to be applied in addition to the keymap's.

test case 1

• users/ahihi is in ~/qmk_firmware
• user.overlay_dir is unset

result: userspace config.h is not included (no rgb timeout)

test case 2

• users/ahihi is in ~/qmk_userspace
• user.overlay_dir is set to ~/qmk_userspace

result: works as expected

test case 3

• users/ahihi is in ~/qmk_firmware
• user.overlay_dir is set to ~/qmk_userspace (which now has an empty users)

result: also works

---

so it seems like even userspace code within the firmware repo does not get included unless user.overlay_dir is set to a separate valid userspace repo. the documentation at https://docs.qmk.fm/feature_userspace makes no mention of this, so i guess this is not intended?

Keyboard Used

kprepublic/bm40hsrgb/rev2

Link to product page (if applicable)

No response

Operating System

macOS 12

qmk doctor Output

Ψ QMK Doctor is checking your environment.
Ψ CLI version: 1.1.5
Ψ QMK home: /Users/ahihi/qmk_firmware
Ψ Detected macOS 12.7.6 (Intel).
Ψ Userspace enabled: False
Ψ Git branch: master
Ψ Repo version: 0.24.8
⚠ Git has unstashed/uncommitted changes.
Ψ - Latest master: 2024-12-29 17:26:38 +0200 (4c41b2fa28) -- init winry315 ahihi keymap with midi
Ψ - Latest upstream/master: 2024-12-27 19:42:54 +0000 (f549948bbd) -- Skip parsing g_led_config when matrix_size is missing (#24739)
Ψ - Latest upstream/develop: None
Ψ - Common ancestor with upstream/master: 2024-12-27 19:42:54 +0000 (f549948bbd) -- Skip parsing g_led_config when matrix_size is missing (#24739)
Ψ - Common ancestor with upstream/develop: None
Ψ All dependencies are installed.
Ψ Found arm-none-eabi-gcc version 12.3.1
Ψ Successfully compiled using arm-none-eabi-gcc
Ψ Successfully tested arm-none-eabi-binutils using arm-none-eabi-size
Ψ Found avr-gcc version 13.3.0
Ψ Successfully compiled using avr-gcc
Ψ Successfully tested avr-binutils using avr-size
Ψ Found avrdude version 8.0
Ψ Found dfu-programmer version 0.7.2
Ψ Found dfu-util version 0.11
Ψ Submodules are up to date.
Ψ Submodule status:
Ψ - lib/chibios: 2024-02-17 19:20:06 +0000 --  (be44b3305f)
Ψ - lib/chibios-contrib: 2024-04-03 20:39:24 +0800 --  (77cb0a4f)
Ψ - lib/googletest: 2021-06-11 06:37:43 -0700 --  (e2239ee6)
Ψ - lib/lufa: 2022-08-26 12:09:55 +1000 --  (549b97320)
Ψ - lib/vusb: 2022-06-13 09:18:17 +1000 --  (819dbc1)
Ψ - lib/printf: 2022-06-29 23:59:58 +0300 --  (c2e3b4e)
Ψ - lib/pico-sdk: 2023-02-12 20:19:37 +0100 --  (a3398d8)
Ψ - lib/lvgl: 2022-04-11 04:44:53 -0600 --  (e19410f8)
Ψ QMK is ready to go, but minor problems were found

Is AutoHotKey / Karabiner installed

• AutoHotKey (Windows)
• Karabiner (macOS)

Other keyboard-related software installed

n/a

Additional Context

No response