Update Dapr CLI/runtime version validation

[philliphoff]

The current extension attempts to validate that Dapr has been installed and initialized. However, that logic is fairly old (e.g. looking for the Dapr Docker container instead of using the now available runtime version number) and did not work for locally-built versions of the Dapr CLI (which uses the semver-incompatible 'edge' string).

The new logic offers more comprehensive validation (e.g. minimum version checks as well as broader enforcement) and refreshes the messaging for when invalid versions are found. Much of the logic is borrowed from vscode-tye.

Shown when no (compatible) version of the CLI is found:

Shown when no (compatible) version of the runtime is found:

Shown when Dapr is installed and initialized but no applications are running:

Shown when attempting to run a dapr or daprd task when there is an incompatibility:

Resolves: #171

[alexdresko]

@philliphoff Any chance we can fix these conflicts and smash the merge button?

[pratiksanglikar]

Looks good to me, just one nitpicking comment for updating a variable name.