api.md: direct TOC links to new publicapi docs location

This change updates the existing api.md TOC links to point at the new
publicapi folder/files. It also removes the body of the docs from the
file, to avoid the docs becoming out of sync.

This change also renames overview.md to readme.md.

Updates tailscale/corp#19526

Signed-off-by: Charlotte Brandhorst-Satzkorn <charlotte@tailscale.com>

publicapi/device.md

@@ -236,8 +236,6 @@ The API exposes two methods for dealing with subnet routes:
 - Get routes: [`GET /api/v2/device/{deviceID}/routes`](#get-device-routes) to fetch lists of advertised and enabled routes for a device
 - Set routes: [`POST /api/v2/device/{deviceID}/routes`](#set-device-routes) to set enabled routes for a device
 
-<a name="device-get"></a>
-
 ## Get device
 
 ```http
@@ -295,8 +293,6 @@ curl "https://api.tailscale.com/api/v2/device/12345?fields=all" \
 }
 ```
 
-<a href="device-delete"></a>
-
 ## Delete device
 
 ```http
@@ -336,8 +332,6 @@ HTTP/1.1 501 Not Implemented
 {"message":"cannot delete devices outside of your tailnet"}
 ```
 
-<a href="expire-device-key"></a>
-
 ## Expire a device's key
 
 ```http
@@ -372,8 +366,6 @@ HTTP/1.1 200 OK
 
 ## Routes
 
-<a href="device-routes-get">
-
 ## Get device routes
 
 ```http
@@ -409,8 +401,6 @@ Returns the enabled and advertised subnet routes for a device.
 }
 ```
 
-<a href="device-routes-post"></a>
-
 ## Set device routes
 
 ```http
@@ -458,8 +448,6 @@ Returns the enabled and advertised subnet routes for a device.
 
 ## Authorize
 
-<a href="#device-authorized-post"></a>
-
 ## Authorize device
 
 ```http
@@ -502,8 +490,6 @@ The response is 2xx on success. The response body is currently an empty JSON obj
 
 ## Tags
 
-<a href="device-tags-post"></a>
-
 ## Update device tags
 
 ```http
@@ -562,8 +548,6 @@ If the tags supplied in the `POST` call do not exist in the tailnet policy file,
 
 ## Keys
 
-<a href="device-key-post"></a>
-
 ## Update device key
 
 ```http

publicapi/tailnet.md

@@ -64,8 +64,6 @@ The policy file is expressed using "[HuJSON](https://github.com/tailscale/hujson
 Most policy file API methods can also return regular JSON for compatibility with other tools.
 Learn more about [network access controls](https://tailscale.com/kb/1018/).
 
-<a href="tailnet-acl-get"></a>
-
 ## Get Policy File
 
 ```http
@@ -203,8 +201,6 @@ In addition, errors and warnings are returned.
 }
 ```
 
-<a href="tailnet-acl-post"></a>
-
 ## Update policy file
 
 ```http
@@ -325,8 +321,6 @@ A successful response returns an HTTP status of '200' and the modified tailnet p
 }
 ```
 
-<a href="tailnet-acl-preview-post"></a>
-
 ## Preview policy file rule matches
 
 ```http
@@ -418,8 +412,6 @@ The response also echoes the `type` and `previewFor` values supplied in the requ
 }
 ```
 
-<a href="tailnet-acl-validate-post"></a>
-
 ## Validate and test policy file
 
 ```http
@@ -526,8 +518,6 @@ any groups that are used in the policy file that are not being synced from SCIM.
 
 ## Devices
 
-<a href="tailnet-devices"></a>
-
 ## List tailnet devices
 
 ```http
@@ -643,8 +633,6 @@ The remaining three methods operate on auth keys and API access tokens.
 }
 ```
 
-<a href="tailnet-keys-get"></a>
-
 ## List tailnet keys
 
 ```http
@@ -684,8 +672,6 @@ Returns a JSON object with the IDs of all active keys.
 }
 ```
 
-<a href="tailnet-keys-post"></a>
-
 ## Create auth key
 
 ```http
@@ -783,8 +769,6 @@ It holds the capabilities specified in the request and can no longer be retrieve
 }
 ```
 
-<a href="tailnet-keys-key-get"></a>
-
 ## Get key
 
 ```http
@@ -845,8 +829,6 @@ Response for a revoked (deleted) or expired key will have an `invalid` field set
 }
 ```
 
-<a href="tailnet-keys-key-delete"></a>
-
 ## Delete key
 
 ```http
@@ -876,8 +858,6 @@ curl -X DELETE 'https://api.tailscale.com/api/v2/tailnet/example.com/keys/k12345
 
 This returns status 200 upon success.
 
-<a href="tailnet-dns"></a>
-
 ## DNS
 
 The tailnet DNS methods are provided for fetching and modifying various DNS settings for a tailnet.
@@ -886,8 +866,6 @@ Learn more about [DNS in Tailscale](https://tailscale.com/kb/1054/).
 
 ## Nameservers
 
-<a href="tailnet-dns-nameservers-get"></a>
-
 ## Get nameservers
 
 ```http
@@ -917,8 +895,6 @@ curl "https://api.tailscale.com/api/v2/tailnet/example.com/dns/nameservers" \
 }
 ```
 
-<a href="tailnet-dns-nameservers-post"></a>
-
 ## Set nameservers
 
 ```http
@@ -989,8 +965,6 @@ The response is a JSON object containing the new list of nameservers and the sta
 
 ## Preferences
 
-<a href="tailnet-dns-preferences-get"></a>
-
 ## Get DNS preferences
 
 ```http
@@ -1020,8 +994,6 @@ curl "https://api.tailscale.com/api/v2/tailnet/example.com/dns/preferences" \
 }
 ```
 
-<a href="tailnet-dns-preferences-post"></a>
-
 ## Set DNS preferences
 
 ```http
@@ -1085,8 +1057,6 @@ If there are DNS servers, this returns the MagicDNS status:
 
 ## Search Paths
 
-<a href="tailnet-dns-searchpaths-get"></a>
-
 ## Get search paths
 
 ```http
@@ -1116,8 +1086,6 @@ curl "https://api.tailscale.com/api/v2/tailnet/example.com/dns/searchpaths" \
 }
 ```
 
-<a href="tailnet-dns-searchpaths-post"></a>
-
 ## Set search paths
 
 ```http