Update docs for mautrix bridges (follow-up) (#3924)

* Update docs/configuring-playbook-bridge-mautrix-telegram.md

- Add a link to the official documentation on authentication
- Create subsections in the section "Usage"
- Update the usage based on d33701428d/bridges/python/telegram/authentication.md

Signed-off-by: Suguru Hirahara <acioustick@noreply.codeberg.org>

* Update docs/configuring-playbook-bridge-mautrix-twitter.md

- Remove a duplicated "optional" label
- Replace the instruction with a link to the official documentation on authentication

Signed-off-by: Suguru Hirahara <acioustick@noreply.codeberg.org>

* Update docs/configuring-playbook-bridge-appservice-kakaotalk.md

- Adopt a common introduction
- Move the warning message down

Signed-off-by: Suguru Hirahara <acioustick@noreply.codeberg.org>

* Update docs/configuring-playbook-bridge-mautrix-discord.md

As our instruction on usage has been outdated compared to the latest one (cf. d33701428d/bridges/go/discord/authentication.md), let alone confusing in the first place as our instruction on logging in and bridging have been mixed, this commit updates our instruction based on the latest official one.

Signed-off-by: Suguru Hirahara <acioustick@noreply.codeberg.org>

* Update docs/configuring-playbook-bridge-mautrix-gmessages.md: add a link to the official documentation on authentication

Based on d33701428d/bridges/go/gmessages/authentication.md

Signed-off-by: Suguru Hirahara <acioustick@noreply.codeberg.org>

* Update docs for mautrix-meta bridges: add links to the official documentation on authentication

Based on d33701428d/bridges/go/meta/authentication.md

Signed-off-by: Suguru Hirahara <acioustick@noreply.codeberg.org>

* Update docs/configuring-playbook-bridge-mautrix-signal.md: add a link to the official documentation on authentication

Signed-off-by: Suguru Hirahara <acioustick@noreply.codeberg.org>

* Update docs/configuring-playbook-bridge-mautrix-slack.md

Based on d33701428d/bridges/go/slack/authentication.md

The instruction has been obsolete since 25b4006035

Signed-off-by: Suguru Hirahara <acioustick@noreply.codeberg.org>

* Update docs/configuring-playbook-bridge-mautrix-googlechat.md

Based on d33701428d/bridges/python/googlechat/authentication.md

Signed-off-by: Suguru Hirahara <acioustick@noreply.codeberg.org>

* Update docs/configuring-playbook-bridge-mautrix-bridges.md: add information about troubleshooting

Signed-off-by: Suguru Hirahara <acioustick@noreply.codeberg.org>

* Update docs for mautrix bridges: add descriptions for each mautrix bridge about the bridges behavior after logging in

Based on d33701428d

Signed-off-by: Suguru Hirahara <acioustick@noreply.codeberg.org>

* Update docs for mautrix bridges: add instruction for sending "help" to the bot to the common guide

Signed-off-by: Suguru Hirahara <acioustick@noreply.codeberg.org>

* Update docs/configuring-playbook-bridge-mautrix-hangouts.md: adopt a common description about usage

Signed-off-by: Suguru Hirahara <acioustick@noreply.codeberg.org>

* Update docs/configuring-playbook-bridge-mautrix-whatsapp.md

- Update the note about linked devices that they will be logged out if the phone is not used over two weeks: the note has been obsolete since 0860109d05
- Adopt a common description about usage

Signed-off-by: Suguru Hirahara <acioustick@noreply.codeberg.org>

* Update docs for mautrix bridges: fix the internal anchor link

Regression by 4b2e066a61

Signed-off-by: Suguru Hirahara <acioustick@noreply.codeberg.org>

* Update docs/configuring-playbook-bridge-mautrix-bridges.md: add a note about the official docs

Signed-off-by: Suguru Hirahara <acioustick@noreply.codeberg.org>

* Update docs/configuring-playbook-bridge-go-skype-bridge.md: adopt the common description

As the bridge was created based on mautrix-whatsapp, this commit adopts the common descriptions for mautrix bridges and ones based on them such as matrix-appservice-kakaotalk and beeper-linkedin

Signed-off-by: Suguru Hirahara <acioustick@noreply.codeberg.org>

---------

Signed-off-by: Suguru Hirahara <acioustick@noreply.codeberg.org>
Co-authored-by: Suguru Hirahara <acioustick@noreply.codeberg.org>

docs/configuring-playbook-bridge-mautrix-bridges.md

@@ -2,6 +2,8 @@
 
 The playbook can install and configure various [mautrix](https://github.com/mautrix) bridges (twitter, discord, signal, googlechat, etc.), as well as many other (non-mautrix) bridges. This is a common guide for configuring mautrix bridges.
 
+The author of the bridges maintains [the official docs](https://docs.mau.fi/bridges/index.html), whose source code is available at [mautrix/docs](https://github.com/mautrix/docs) repository on GitHub. You may as well to refer it while configuring them.
+
 You can see each bridge's features on the `ROADMAP.md` file in its corresponding mautrix repository.
 
 ## Adjusting the playbook configuration
@@ -159,6 +161,8 @@ To use the bridge, you need to start a chat with `@SERVICENAMEbot:example.com` (
 
 For details about the next steps, refer to each bridge's individual documentation page.
 
+Send `help` to the bot to see the available commands.
+
 If you run into trouble, check the [Troubleshooting](#troubleshooting) section below.
 
 ### Set up Double Puppeting (optional)
@@ -204,4 +208,6 @@ When using this method, **each user** that wishes to enable Double Puppeting nee
 
 For troubleshooting information with a specific bridge, please see the playbook documentation about it (some other document in in `docs/`) and the upstream ([mautrix](https://github.com/mautrix)) bridge documentation for that specific bridge.
 
-Reporting bridge bugs should happen upstream, in the corresponding mautrix repository, not to us.
+If the bridge's bot doesn't accept the invite to a chat, refer [the official troubleshooting page](https://docs.mau.fi/bridges/general/troubleshooting.html) as well.
+
+If you found bugs in mautrix bridges, they should be reported to the upstream project, in the corresponding mautrix repository, not to us.