Is HMAC padding the same as bcrypt?
This is not padding, nor is it related to the concept.

The output from the bcrypt library you're using is in a format inspired by Linux crypt(3) format. Dollar signs are field separators. 2a is the algorithm identifier. The full list is:

ID  | Method
─────────────────────────────────────────────────────────
1   | MD5
2a  | Blowfish (not in mainline glibc; added in some
    | Linux distributions)
5   | SHA-256 (since glibc 2.7)
6   | SHA-512 (since glibc 2.7)


The second field, 10, is the strength factor; I believe this corresponds to $2^{10}$ iterations of the algorithm. The salt and hash are stored concatenated with one-another — they are both fixed widths (128 bits for the salt, 184 bits for the hash), so it is easy to extract them.