feat: flip swap mechanism — MD as primary, RST as override (Phase 1)

This is the first of three phases inverting the per-page swap mechanism
so MD becomes the canonical primary and RST becomes the rare override.

Phase 1 — file renames + conf.py exclude_patterns flip only:
- Rename docs/**/md-<stem>.md to docs/**/<stem>.md (drop md- prefix)
  for all 254 stems previously listed in docs/_swap.txt
- Rename docs/**/<stem>.rst to docs/**/rst-<stem>.rst (add rst- prefix)
  for the same 254 stems
- Repurpose docs/_swap.txt as docs/_rst_overrides.txt; initially empty
  comment-only since no pages need the RST fallback right now
- conf.py exclude_patterns flipped: rst-*.rst is now excluded by default
  instead of md-*.md
- conf.py runtime-artifact references updated to _rst_override_state.json
  and _md_exclude.txt (Phase 2 will rewrite swap_sources.py to produce
  these names; for now no swap script runs because overrides list is empty)

Phase 2 (next commit on this branch) will rewrite scripts/swap_sources.py
with inverted rename direction, delete scripts/import_myst.py + tests, and
update tests/test_swap_sources.py for the new semantics.

Phase 3 will be the cleanup pass and ready-for-review flip.

Generated by robots https://vyos.io

1 files changed, 0 insertions, 113 deletions

diff --git a/docs/installation/md-image.md b/docs/installation/md-image.md
deleted file mode 100644
index a0fc89d4..00000000
--- a/docs/installation/md-image.md
+++ /dev/null
@@ -1,113 +0,0 @@
----
-lastproofread: '2026-01-26'
----
-
-(image-mgmt)=
-
-# Image Management
-
-VyOS uses an image-based installation that creates a directory for each image
-on the storage device you select during installation.
-
-The boot device has the following directory structure:
-
-```none
-/
-/boot
-/boot/grub
-/boot/2025.07.16-0020-rolling.squashfs
-```
-
-The image directory contains the system kernel, a compressed root filesystem
-image, and a directory for persistent storage (such as configuration). During
-boot, the system extracts the OS image into memory and mounts the appropriate
-live-rw subdirectories to provide persistent storage for system configuration.
-
-This process ensures that the system always boots to a known working state,
-since the OS image is fixed and non-persistent. You can also install multiple
-VyOS releases on the same storage device. You can manually select the image at
-boot if needed, but the system boots the default image by default.
-
-```{opcmd} show system image
-
-List all available system images which can be booted on the current system.
-
-:::{code-block} none
-vyos@vyos:~$ show system image
-Name                     Default boot    Running
------------------------  --------------  ---------
-2025.07.16-0020-rolling  Yes             Yes
-1.4.1
-1.4.0
-:::
-```
-```{opcmd} delete system image [image-name]
-
-   Delete unused images from the system. You can specify an optional image name
-   to delete. Use the {opcmd}`show system image` command to list available
-   images.
-
-   :::{code-block} none
-   vyos@vyos:~$ delete system image
-   The following images are installed:
-           1: 2025.07.16-0020-rolling (running) (default boot)
-           2: 1.4.1
-           3: 1.4.0
-   Select an image to delete: 3
-   Do you really want to delete the image 1.4.0? [y/N] y
-   The image "1.4.0" was successfully deleted
-   :::
-```
-
-
-```{opcmd} show version
-
-Show current system image version.
-
-:::{code-block} none
-vyos@vyos:~$ show version
-Version:          VyOS 2025.07.16-0020-rolling
-Release train:    current
-Release flavor:   generic
-
-Built by:         autobuild@vyos.net
-Built on:         Wed 16 Jul 2025 00:21 UTC
-Build UUID:       20d432ee-6d55-4ebc-8462-46fe836246c9
-Build Commit ID:  f7ce0d8a692f2d
-
-Architecture:     x86_64
-Boot via:         installed image
-System type:      KVM guest
-Secure Boot:      n/a (BIOS)
-
-Hardware vendor:  QEMU
-Hardware model:   Standard PC (i440FX + PIIX, 1996)
-Hardware S/N:
-Hardware UUID:    b9831d42-c1fe-b2bd-7d3d-49db9418f5c9
-
-Copyright:        VyOS maintainers and contributors
-:::
-```
-
-## System rollback
-
-To roll back to a previous image, first view the available images by using the
-{opcmd}`show system image` command, then select your image with the following
-command:
-
-```{opcmd} set system image default-boot [image-name]
-
-Select the default boot image which will be started on the next boot
-of the system.
-```
-
-Then reboot the system.
-
-:::{note}
-VyOS automatically associates the configuration with each image,
-so you don't need to manage this separately. Each image has its own unique
-configuration copy.
-:::
-
-If you have console access, you can also select the boot image by restarting
-the system and using the GRUB menu at startup.