docs: update simapp inline docs (cosmos#11930)

## Description

ref: cosmos#11362



---

### Author Checklist

*All items are required. Please add a note to the item if the item is not applicable and
please add links to any relevant follow up issues.*

I have...

- [ ] included the correct [type prefix](https://github.com/commitizen/conventional-commit-types/blob/v3.0.0/index.json) in the PR title
- [ ] added `!` to the type prefix if API or client breaking change
- [ ] targeted the correct branch (see [PR Targeting](https://github.com/cosmos/cosmos-sdk/blob/main/CONTRIBUTING.md#pr-targeting))
- [ ] provided a link to the relevant issue or specification
- [ ] followed the guidelines for [building modules](https://github.com/cosmos/cosmos-sdk/blob/main/docs/building-modules)
- [ ] included the necessary unit and integration [tests](https://github.com/cosmos/cosmos-sdk/blob/main/CONTRIBUTING.md#testing)
- [ ] added a changelog entry to `CHANGELOG.md`
- [ ] included comments for [documenting Go code](https://blog.golang.org/godoc)
- [ ] updated the relevant documentation or specification
- [ ] reviewed "Files changed" and left comments if necessary
- [ ] confirmed all CI checks have passed

### Reviewers Checklist

*All items are required. Please add a note if the item is not applicable and please add
your handle next to the items reviewed if you only reviewed selected items.*

I have...

- [ ] confirmed the correct [type prefix](https://github.com/commitizen/conventional-commit-types/blob/v3.0.0/index.json) in the PR title
- [ ] confirmed `!` in the type prefix if API or client breaking change
- [ ] confirmed all author checklist items have been addressed 
- [ ] reviewed state machine logic
- [ ] reviewed API design and naming
- [ ] reviewed documentation is accurate
- [ ] reviewed tests and test coverage
- [ ] manually tested (if applicable)

simd/cmd/testnet.go

@@ -100,7 +100,7 @@ func NewTestnetCmd(mbm module.BasicManager, genBalIterator banktypes.GenesisBala
 	return testnetCmd
 }
 
-// get cmd to initialize all files for tendermint testnet and application
+// testnetInitFilesCmd returns a cmd to initialize all files for tendermint testnet and application
 func testnetInitFilesCmd(mbm module.BasicManager, genBalIterator banktypes.GenesisBalancesIterator) *cobra.Command {
 	cmd := &cobra.Command{
 		Use:   "init-files",
@@ -150,7 +150,7 @@ Example:
 	return cmd
 }
 
-// get cmd to start multi validator in-process testnet
+// testnetStartCmd returns a cmd to start multi validator in-process testnet
 func testnetStartCmd() *cobra.Command {
 	cmd := &cobra.Command{
 		Use:   "start",

test_helpers.go

@@ -256,7 +256,7 @@ func SetupWithGenesisAccounts(t *testing.T, genAccs []authtypes.GenesisAccount,
 	return SetupWithGenesisValSet(t, valSet, genAccs, balances...)
 }
 
-// SetupWithGenesisValSet initializes GenesisState with a single validator and genesis accounts
+// GenesisStateWithSingleValidator initializes GenesisState with a single validator and genesis accounts
 // that also act as delegators.
 func GenesisStateWithSingleValidator(t *testing.T, app *SimApp) GenesisState {
 	t.Helper()
@@ -335,7 +335,7 @@ func AddTestAddrs(app *SimApp, ctx sdk.Context, accNum int, accAmt sdk.Int) []sd
 	return addTestAddrs(app, ctx, accNum, accAmt, createRandomAccounts)
 }
 
-// AddTestAddrs constructs and returns accNum amount of accounts with an
+// AddTestAddrsIncremental constructs and returns accNum amount of accounts with an
 // initial balance of accAmt in random order
 func AddTestAddrsIncremental(app *SimApp, ctx sdk.Context, accNum int, accAmt sdk.Int) []sdk.AccAddress {
 	return addTestAddrs(app, ctx, accNum, accAmt, createIncrementalAccounts)