r/f-b-arr: Configure Fluent Bit for Servarr logs

The _fluent-bit-servarr_ role creates a configuration file for Fluent
Bit to read and parse logs from Radarr, Sonarr, and Prowlarr.  These
logs can then be sent to an output by defining the
`fluent_bit_servarr_outputs` variable.

roles/fluent-bit-servarr/vars/main.yml

@@ -0,0 +1,45 @@
+servarr_logs:
+- /var/log/prowlarr/*.txt
+- /var/log/radarr/*.txt
+- /var/log/sonarr/*.txt
+
+fluent_bit_servarr_config:
+  multiline_parsers:
+  - name: multiline_servarr
+    type: regex
+    flush_timeout: 500
+    rules:
+    - state: start_state
+      regex: ^\d{4}-\d{2}-\d{2} [ 0-2]?\d:\d{2}:\d{2}\.\d+\|
+      next_state: cont
+    - state: cont
+      regex: ^(?!\d{4}-\d{2}-\d{2} [ 0-2]?\d:\d{2}:\d{2}\.\d+\|).*
+      next_state: cont
+
+  parsers:
+  - name: servarr
+    format: regex
+    regex: /^(?<timestamp>\d{4}-\d{2}-\d{2} [ 0-2]?\d:\d{2}:\d{2}\.\d+)\|(?<level>[^|]+)\|(?<logger>[^|]+)\|(?<log>.*)/m
+    time_key: timestamp
+    time_format: '%Y-%m-%d %H:%M:%S.%L'
+
+  pipeline:
+    inputs:
+    - name: tail
+      alias: servarr
+      tag: servarr
+      path: '{{ servarr_logs | join(",") }}'
+      path_key: filename
+      multiline.parser: multiline_servarr
+      db: /var/lib/fluent-bit/servarr.db
+      read_from_head: true
+
+    filters:
+    - name: parser
+      alias: servarr
+      match: servarr
+      key_name: log
+      parser: servarr
+      reserve_data: true
+
+    outputs: '{{ fluent_bit_servarr_outputs }}'