feat(api): feature flags (#7356)

* feat(api): feature API proto definitions

* update proto based on discussion with @livio-a

* cleanup old feature flag stuff

* authz instance queries

* align defaults

* projection definitions

* define commands and event reducers

* implement system and instance setter APIs

* api getter implementation

* unit test repository package

* command unit tests

* unit test Get queries

* grpc converter unit tests

* migrate the V1 features

* migrate oidc to dynamic features

* projection unit test

* fix instance by host

* fix instance by id data type in sql

* fix linting errors

* add system projection test

* fix behavior inversion

* resolve proto file comments

* rename SystemDefaultLoginInstanceEventType to SystemLoginDefaultOrgEventType so it's consistent with the instance level event

* use write models and conditional set events

* system features integration tests

* instance features integration tests

* error on empty request

* documentation entry

* typo in feature.proto

* fix start unit tests

* solve linting error on key case switch

* remove system defaults after discussion with @eliobischof

* fix system feature projection

* resolve comments in defaults.yaml

---------

Co-authored-by: Livio Spring <livio.a@gmail.com>

internal/feature/level_enumer.go

@@ -0,0 +1,98 @@
+// Code generated by "enumer -type Level -transform snake -trimprefix Level"; DO NOT EDIT.
+
+package feature
+
+import (
+	"fmt"
+	"strings"
+)
+
+const _LevelName = "unspecifiedsysteminstanceorgprojectappuser"
+
+var _LevelIndex = [...]uint8{0, 11, 17, 25, 28, 35, 38, 42}
+
+const _LevelLowerName = "unspecifiedsysteminstanceorgprojectappuser"
+
+func (i Level) String() string {
+	if i < 0 || i >= Level(len(_LevelIndex)-1) {
+		return fmt.Sprintf("Level(%d)", i)
+	}
+	return _LevelName[_LevelIndex[i]:_LevelIndex[i+1]]
+}
+
+// An "invalid array index" compiler error signifies that the constant values have changed.
+// Re-run the stringer command to generate them again.
+func _LevelNoOp() {
+	var x [1]struct{}
+	_ = x[LevelUnspecified-(0)]
+	_ = x[LevelSystem-(1)]
+	_ = x[LevelInstance-(2)]
+	_ = x[LevelOrg-(3)]
+	_ = x[LevelProject-(4)]
+	_ = x[LevelApp-(5)]
+	_ = x[LevelUser-(6)]
+}
+
+var _LevelValues = []Level{LevelUnspecified, LevelSystem, LevelInstance, LevelOrg, LevelProject, LevelApp, LevelUser}
+
+var _LevelNameToValueMap = map[string]Level{
+	_LevelName[0:11]:       LevelUnspecified,
+	_LevelLowerName[0:11]:  LevelUnspecified,
+	_LevelName[11:17]:      LevelSystem,
+	_LevelLowerName[11:17]: LevelSystem,
+	_LevelName[17:25]:      LevelInstance,
+	_LevelLowerName[17:25]: LevelInstance,
+	_LevelName[25:28]:      LevelOrg,
+	_LevelLowerName[25:28]: LevelOrg,
+	_LevelName[28:35]:      LevelProject,
+	_LevelLowerName[28:35]: LevelProject,
+	_LevelName[35:38]:      LevelApp,
+	_LevelLowerName[35:38]: LevelApp,
+	_LevelName[38:42]:      LevelUser,
+	_LevelLowerName[38:42]: LevelUser,
+}
+
+var _LevelNames = []string{
+	_LevelName[0:11],
+	_LevelName[11:17],
+	_LevelName[17:25],
+	_LevelName[25:28],
+	_LevelName[28:35],
+	_LevelName[35:38],
+	_LevelName[38:42],
+}
+
+// LevelString retrieves an enum value from the enum constants string name.
+// Throws an error if the param is not part of the enum.
+func LevelString(s string) (Level, error) {
+	if val, ok := _LevelNameToValueMap[s]; ok {
+		return val, nil
+	}
+
+	if val, ok := _LevelNameToValueMap[strings.ToLower(s)]; ok {
+		return val, nil
+	}
+	return 0, fmt.Errorf("%s does not belong to Level values", s)
+}
+
+// LevelValues returns all values of the enum
+func LevelValues() []Level {
+	return _LevelValues
+}
+
+// LevelStrings returns a slice of all String values of the enum
+func LevelStrings() []string {
+	strs := make([]string, len(_LevelNames))
+	copy(strs, _LevelNames)
+	return strs
+}
+
+// IsALevel returns "true" if the value is listed in the enum definition. "false" otherwise
+func (i Level) IsALevel() bool {
+	for _, v := range _LevelValues {
+		if i == v {
+			return true
+		}
+	}
+	return false
+}