Move PX4 Guide source into /docs (#24490)

* Add vitepress tree

* Update existing workflows so they dont trigger on changes in the docs path

* Add nojekyll, package.json, LICENCE etc

* Add crowdin docs upload/download scripts

* Add docs flaw checker workflows

* Used docs prefix for docs workflows

* Crowdin obvious fixes

* ci: docs move to self hosted runner

runs on a beefy server for faster builds

Signed-off-by: Ramon Roche <mrpollo@gmail.com>

* ci: don't run build action for docs or ci changes

Signed-off-by: Ramon Roche <mrpollo@gmail.com>

* ci: update runners

Signed-off-by: Ramon Roche <mrpollo@gmail.com>

* Add docs/en

* Add docs assets and scripts

* Fix up editlinks to point to PX4 sources

* Download just the translations that are supported

* Add translation sources for zh, uk, ko

* Update latest tranlsation and uorb graphs

* update vitepress to latest

---------

Signed-off-by: Ramon Roche <mrpollo@gmail.com>
Co-authored-by: Ramon Roche <mrpollo@gmail.com>

docs/en/flight_modes/index.md

@@ -0,0 +1,16 @@
+# Flight Modes
+
+Flight modes provide autopilot support to make it easier to manually fly the vehicle, to automate common tasks such as takeoff and landing, to execute autonomous missions, or to defer flight control to an external system.
+
+For information about flight modes available to specific frames see the following topics:
+
+- [Flight Modes (Multicopter)](../flight_modes_mc/index.md)
+- [Flight Modes (Fixed-Wing)](../flight_modes_fw/index.md)
+- [Flight Modes (VTOL)](../flight_modes_vtol/index.md)
+- [Drive Modes (Differential Rover)](../flight_modes_rover/differential.md)
+- [Drive Modes (Ackermann Rover)](../flight_modes_rover/ackermann.md)
+
+::: info
+The mode sub-topics in this section contain information that is common to all vehicles, but may not be relevant to the normal/default setup.
+Generally you should see the vehicle-specific topics first, and navigate to these generalized topics when it becomes relevant.
+:::