docs: add more extension type URLs (#21885)

Follow-up to #21707 with a focus on back-filling more extension type URLs. Renames extensions_build_config and extensions_metadata to the names in the internal extension registry. For preserve_case, we deprecate the short name with the fully qualified name (both names are valid in the interim).

Risk Level: medium, only preserve_case name changes
Testing: regression
Docs Changes: yes
Release Notes: yes

Signed-off-by: Kuat Yessenov <kuat@google.com>

Mirrored from https://github.com/envoyproxy/envoy @ 7c04dda02a61c4866b6cc7273c776d62dd3fb127

envoy/config/filter/thrift/rate_limit/v2alpha1/rate_limit.proto

@@ -20,7 +20,7 @@ option (udpa.annotations.file_status).package_version_status = FROZEN;
 
 // [#protodoc-title: Rate limit]
 // Rate limit :ref:`configuration overview <config_thrift_filters_rate_limit>`.
-// [#extension: envoy.filters.thrift.ratelimit]
+// [#extension: envoy.filters.thrift.rate_limit]
 
 // [#next-free-field: 6]
 message RateLimit {

envoy/extensions/config/validators/minimum_clusters/v3/minimum_clusters.proto

@@ -11,7 +11,7 @@ option go_package = "github.com/envoyproxy/go-control-plane/envoy/extensions/con
 option (udpa.annotations.file_status).package_version_status = ACTIVE;
 
 // [#protodoc-title: Minimum Clusters]
-// [#extension: envoy.config.validators.minimum_clusters]
+// [#extension: envoy.config.validators.minimum_clusters_validator]
 
 // Validates a CDS config, and ensures that the number of clusters is above the
 // set threshold.

envoy/extensions/filters/network/thrift_proxy/filters/ratelimit/v3/rate_limit.proto

@@ -18,7 +18,7 @@ option (udpa.annotations.file_status).package_version_status = ACTIVE;
 
 // [#protodoc-title: Rate limit]
 // Rate limit :ref:`configuration overview <config_thrift_filters_rate_limit>`.
-// [#extension: envoy.filters.thrift.ratelimit]
+// [#extension: envoy.filters.thrift.rate_limit]
 
 // [#next-free-field: 6]
 message RateLimit {

envoy/extensions/filters/udp/dns_filter/v3/dns_filter.proto

@@ -22,7 +22,7 @@ option (udpa.annotations.file_status).package_version_status = ACTIVE;
 
 // [#protodoc-title: DNS Filter]
 // DNS Filter :ref:`configuration overview <config_udp_listener_filters_dns_filter>`.
-// [#extension: envoy.filters.udp_listener.dns_filter]
+// [#extension: envoy.filters.udp.dns_filter]
 
 // Configuration for the DNS filter.
 message DnsFilterConfig {

envoy/extensions/matching/input_matchers/consistent_hashing/v3/consistent_hashing.proto

@@ -12,7 +12,7 @@ option go_package = "github.com/envoyproxy/go-control-plane/envoy/extensions/mat
 option (udpa.annotations.file_status).package_version_status = ACTIVE;
 
 // [#protodoc-title: Consistent Hashing Matcher]
-// [#extension: envoy.matching.input_matchers.consistent_hashing]
+// [#extension: envoy.matching.matchers.consistent_hashing]
 
 // The consistent hashing matchers computes a consistent hash from the input and matches if the resulting hash
 // is within the configured threshold.

envoy/extensions/matching/input_matchers/ip/v3/ip.proto

@@ -14,7 +14,7 @@ option go_package = "github.com/envoyproxy/go-control-plane/envoy/extensions/mat
 option (udpa.annotations.file_status).package_version_status = ACTIVE;
 
 // [#protodoc-title: IP matcher]
-// [#extension: envoy.matching.input_matchers.ip]
+// [#extension: envoy.matching.matchers.ip]
 
 // This input matcher matches IPv4 or IPv6 addresses against a list of CIDR
 // ranges. It returns true if and only if the input IP belongs to at least one