DYNCFG: dynamically configured alerts (#16779)

* cleanup alerts

* fix references

* fix references

* fix references

* load alerts once and apply them to each node

* simplify health_create_alarm_entry()

* Compile without warnings with compiler flags:

   -Wall -Wextra -Wformat=2 -Wshadow -Wno-format-nonliteral -Winit-self

* code re-organization and cleanup

* generate patterns when applying prototypes; give unique dyncfg names to all alerts

* eval expressions keep the source and the parsed_as as STRING pointers

* renamed host to node in dyncfg ids

* renamed host to node in dyncfg ids

* add all cloud roles to the list of parsed X-Netdata-Role header and also default to member access level

* working functionality

* code re-organization: moved health event-loop to a new file, moved health globals to health.c

* rrdcalctemplate is removed; alert_cfg is removed; foreach dimension is removed; RRDCALCs are now instanciated only when they are linked to RRDSETs

* dyncfg alert prototypes initialization for alerts

* health dyncfg split to separate file

* cleanup not-needed code

* normalize matches between parsing and json

* also detect !* for disabled alerts

* dyncfg capability disabled

* Store alert config part1

* Add rrdlabels_common_count

* wip health variables lookup without indexes

* Improve rrdlabels_common_count by reusing rrdlabels_find_label_with_key_unsafe with an additional parameter

* working variables with runtime lookup

* working variables with runtime lookup

* delete rrddimvar and rrdfamily index

* remove rrdsetvar; now all variables are in RRDVARs inside hosts and charts

* added /api/v1/variable that resolves a variable the same way alerts do

* remove rrdcalc from eval

* remove debug code

* remove duplicate assignment

* Fix memory leak

* all alert variables are now handled by alert_variable_lookup() and EVAL is now independent of alerts

* hide all internal structures of EVAL

* Enable -Wformat flag

Signed-off-by: Tasos Katsoulas <tasos@netdata.cloud>

* Adjust binding for calculation, warning, critical

* Remove unused macro

* Update config hash id

* use the right info and summary in alerts log

* use synchronous queries for alerts

* Handle cases when config_hash_id is missing from health_log

* remove deadlock from health worker

* parsing to json payload for health alert prototypes

* cleaner parsing and avoiding memory leaks in case of duplicate members in json

* fix left-over rename of function

* Keep original lookup field to send to the cloud
Cleanup / rename function to store config
Remove unused DEFINEs, functions

* Use ac->lookup

* link jobs to the host when the template is registered; do not accept running a function without a host

* full dyncfg support for health alerts, except action TEST

* working dyncfg additions, updates, removals

* fixed missing source, wrong status updates

* add alerts by type, component, classification, recipient and module at the /api/v2/alerts endpoint

* fix dyncfg unittest

* rename functions

* generalize the json-c parser macros and move them to libnetdata

* report progress when enabling and disabling dyncfg templates

* moved rrdcalc and rrdvar to health

* update alarms

* added schema for alerts; separated alert_action_options from rrdr_options; restructured the json payload for alerts

* enable parsed json alerts; allow sending back accepted but disabled

* added format_version for alerts payload; enables/disables status now is also inheritted by the status of the rules; fixed variable names in json output

* remove the RRDHOST pointer from DYNCFG

* Fix command field submitted to the cloud

* do not send updates to creation requests, for DYNCFG jobs

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Signed-off-by: Tasos Katsoulas <tasos@netdata.cloud>
Co-authored-by: Stelios Fragkakis <52996999+stelfrag@users.noreply.github.com>
Co-authored-by: Tasos Katsoulas <tasos@netdata.cloud>
Co-authored-by: ilyam8 <ilya@netdata.cloud>